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(p. 1) What Is Acceptance and Commitment Therapy (ACT)? 

(p. 1) What Is Acceptance and Commitment Therapy (ACT)?
(p. 1) What Is Acceptance and Commitment Therapy (ACT)?

Michael P. Twohig

, Michael E. Levin

, and Clarissa W. Ong

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date: 24 September 2020

We will give a broad overview of ACT in this first chapter. This will include how ACT fits into the broader empirically supported therapy and evidence-based practice literature, such as how ACT overlaps with other treatments and defining qualities that distinguish it. We will also give you a primer on the basics of ACT theory, providing you with an overall sense of the model. By the end of the chapter, we want you to have a sense of what ACT is and of the basic concepts and terms used throughout this book.

Is This a Reasonable Choice for Therapy?

There are many factors that go into choosing a therapy for a given client and as part of your broader collection of approaches you will use. You might consider what the evidence base is for the specific presenting concern, whether it fits well with your existing training and approach to working with clients, and whether it applies well to the clients you serve. Part of our enthusiasm for ACT is due to how well it can fit for so many therapists as (1) an empirically supported treatment that (2) applies to a wide range of clients with various struggles and (3) is flexible in how it fits a variety of therapeutic approaches and backgrounds. There is also a style to ACT that fits quite well for certain clients. Understanding how to do ACT well and when to use it should help you professionally.

ACT is an empirically supported treatment (EST)

Over the past two decades, research on ACT has skyrocketed, with over 300 published randomized control trials (RCTs) to date demonstrating the efficacy of ACT for a range of problems including depression, anxiety disorders, obsessive-compulsive and related disorders, psychosis, addictions, eating disorders, stigma, (p. 2) stress and burnout, chronic pain, weight loss, and coping with or managing medical conditions (Association for Contextual Behavioral Science [ACBS], 2019). Meta-analyses of ACT show that it produces large effect sizes when compared to waitlists, and small to medium effect sizes relative to active control conditions such as treatment-as-usual (A-Tjak et al., 2015; Bluett, Homan, Morrison, Levin, & Twohig, 2014; Hughes, Clark, Colclough, Dale, & McMillan, 2017; Lee, An, Levin, & Twohig, 2015). Compared to other empirically supported cognitive-behavioral therapies (CBTs), ACT generally performs equivalently (Bluett et al., 2014), with a slight, nonsignificant trend suggesting ACT may have stronger effects than other CBTs and established treatments in some cases (A-Tjak et al., 2015; Lee et al., 2015). As of 2019, the official list of ESTs from Division 12 of the American Psychological Association indicated that ACT is evidence-based for anxiety disorders, depression, chronic pain, psychosis, and obsessive-compulsive disorder (although this list is slow and conservative to update). Thus, the evidence base of ACT is positive, continues to grow exponentially, and is consistent with evidence-based practice.

Broad applicability to clients

As you will find throughout this book, ACT is defined functionally in terms of a set of mindfulness, acceptance, and values-based processes applied to target maladaptive ways in which clients “get stuck” in their lives. The ways clients get stuck can be found across a wide range of presentations and settings, and the ways we help clients get unstuck in ACT similarly work well across a breadth of areas. Just like a client might get stuck in an avoidance cycle with their depression, they can get stuck with cravings, anxiety, pain, body image concerns, adhering to a medication, and so on. The evidence bears this out too showing these maladaptive processes (e.g., emotional avoidance, inaction, rumination) targeted by ACT predict a wide range of problems, and using ACT to target these processes leads to improvements in a variety of clinical presentations (A-Tjak et al., 2015; Bluett et al., 2014; Hayes, Levin, Plumb-Vilardaga, Villatte, & Pistorello, 2013; Twohig & Levin, 2017). In later chapters, we will explore how to assess and conceptualize cases based on the ACT model, but suffice it to say, ACT can be applied to a range of clients and is thus likely to be useful in whatever setting you work in.

ACT is flexible in applying to a wide range of practitioners

As a functional approach, ACT not only applies to a wide range of clients but also fits a wide range of practitioners. There are many ways to do ACT, such that it can align with different personal styles, therapeutic strategies, settings, and clients. What matters is function—helping clients be more mindful and accepting of their experiences while doing what is meaningful and effective in the moment. This can look deeply experiential and relational, psychoeducational (p. 3) and didactic, and anywhere in between depending on various factors. Therapists regularly tell us how they use their existing skills and strategies from other treatments to do ACT (e.g., psychodynamic, humanistic, cognitive-behavioral, systems, multicultural) or that they recognize techniques used in ACT protocols from other approaches. What matters is that your therapist behaviors serve to move ACT targets (which we often refer to as “function over form”). This flexibility, at times, can feel overwhelming given all the choices available, but the flexibility also means it is a lot more likely that ACT can be fitted to the type of therapy you practice and clients with whom you work. If you are in a primary care setting, rest assured, ACT can be adapted to that type of brief, focused format. If you are in community mental health, ACT can be adapted to the unique needs of clients from various backgrounds. As a reflection of this flexibility, ACT is increasingly being adopted by professions across and outside of healthcare, including behavior analysis, social work, nursing, education, criminal justice, athletics, workplaces, and so on.

This book aims to give an introduction to ACT as an evidence-based, flexible treatment that can be applied in a variety of ways with a breadth of clients by providing a general but structured protocol. This will give you a jumping-off point to learn how to do ACT, developing competencies and strategies that you can continue to adapt and flexibly apply, based on your understanding of ACT, clinical style, setting, and clients. Before we go into how to do ACT, we will define what ACT is within the broader evidence-based therapy field. In a sense, this foundation of what ACT is will help you grasp how the engine of ACT works, so when potential issues arise (e.g., how to respond when a client does X), you will have the prerequisite knowledge to steer your therapy session effectively while staying consistent with the ACT model.

ACT Is Part of the CBT Tradition

ACT is a modern form of CBT. Readers may be familiar with debates in the early 2000s regarding how ACT overlaps, versus is distinct from, other existing CBT approaches (e.g., Hayes, 2004; Hayes et al., 2013; Hofmann & Asmundson, 2008). Part of this grew out of attempts to define a “third wave” of modern CBTs that included ACT among other newer CBTs that incorporated mindfulness and acceptance procedures, often with a behavior analytic foundation (e.g., dialectical behavior therapy, functional analytic psychotherapy, modern forms of behavioral activation; Hayes, 2004). This led some to question whether treatments like ACT represented something new and different within CBT and how it was situated within the broader field. However, as of 2020, these discussions are largely historical and the relation between ACT and traditional CBT has been partially clarified.

In broad strokes, ACT can be understood as being part of the CBT tradition that includes an integration of behavior therapy and its underlying basic behavioral science (i.e., respondent and operant conditioning) with modern scientific (p. 4) accounts that further address the role of internal processes such as cognitions and emotions. Like other forms of CBT, ACT recognizes that an adequate approach to treating clients has to include an account that not only leverages what we know about human behavior and how to influence it but also addresses the complex interplay of cognitions, emotions, and other internal factors that influence our actions and experiences.

ACT also overlaps with defining aspects of CBT, including imposing general parameters for treatment that give it structure amidst flexibility in its application. These parameters include (1) focusing treatment on collaboratively developed clinical targets and goals within a sensitive time period (i.e., treatment is time-limited and appropriate to clinical needs), (2) being guided by ongoing assessment and tracking of client functioning, and (3) being driven by a case conceptualization that is continually updated. ACT differs from other CBTs in terms of the degree of rigid adherence to protocols that are necessary and sufficient for defining a treatment (i.e., fidelity to protocols). However, as this book shows, ACT can be implemented with a protocol that includes parameters around the number, focus, and content of sessions. ACT is just more flexible in terms of the degree to which a protocol is needed and the degree of flexibility within a protocol.

That said, ACT also differs from other forms of CBT as it has traditionally been practiced and taught. Most often, these differences between ACT and traditional CBT are discussed in terms of how ACT conceptualizes and addresses clients’ internal experiences (Hayes, 2004). For example, some forms of CBT might seek to reduce and replace anxious thoughts that lead to avoiding feared situations so a client can approach these situations because the thoughts have changed (i.e., changing thoughts to change actions). In contrast, ACT would seek to reduce the effect of anxious thoughts on one’s behavior so that feared situations are approached despite having these thoughts (i.e., reducing the impact of thoughts on actions). Before we go into how these differences affect clinical approach, it is worth exploring the deeper philosophical differences between traditional CBT and ACT in how human behavior is studied, conceptualized, and addressed (Hayes et al., 2013).

Functional Contextualism as the Foundation for ACT

ACT is based on a philosophy of science called “functional contextualism” (Hayes, Hayes, & Reese, 1988), which provides the foundation for how we develop and organize our knowledge about human behavior. Although this can feel esoteric at times, by the time you finish this section, we hope we will have made a good case for why this understanding matters and how it can be useful to your learning ACT. These functional contextual assumptions provide the building blocks for the treatment strategies you will learn throughout this book.

(p. 5) Behavior-in-context as the unit of analysis

A defining feature of functional contextualism is its focus on understanding behavior in context. If we think of behavior as anything a person does (including thoughts, feelings, and other events we cannot see), context refers to everything else external to that in terms of situation (time, location, other people’s reaction, etc.) and history (what has happened in the past before and after the given behavior). From a functional contextual perspective, we can only understand a given action if we include context. For example, the thought “I’m worthless” cannot be removed and studied in isolation. We have to understand it by looking at when the thought comes up, what the person’s history with the thought is, and what happens after the thought occurs.

This might still feel like intellectual jargon, but it echoes down into how thoughts are treated in ACT. There are not rational thoughts that are healthy and irrational thoughts that need to be changed to support healthy functioning. Rather, these are all just behaviors occurring in specific contexts. Someone might have the thought “I’m worthless” after waving at another person who does not reciprocate. This person might have a rich history of believing and treating this thought as factually true, as well as a history of important loved ones telling them they are “worthless.” This history might lead to withdrawing from others out of shame for being truly “worthless,” which in the past has led to successfully escaping these feelings of shame for a brief period of time. From a functional contextual perspective, there is a lot to “I’m worthless” that has to do with these contextual factors (i.e., what happens around this thought currently and in the past). These contextual factors help us understand how “I’m worthless” functions and how we might change these behaviors to support healthier functioning. For example, we could try to reduce the frequency of the thought by targeting the contexts in which it occurs (e.g., avoiding awkward hand waves, only waving at people they know can see them), change the content of the thought by teaching other ways of thinking in those situations (e.g., identifying other reasons someone might not wave back), or change the function of the thought by changing how one relates to it (e.g., noticing it as just a thought). At its core, the idea is that we do not fully understand any given behavior (including inner experiences like thoughts and feelings) until we know the current and historical context.

Prediction and influence is the goal

This leads to the second key feature of functional contextualism: its emphasis on not only predicting but also influencing (i.e., changing) behavior. We can only say we understand a behavior if we can both predict and influence it.

Often in psychology we focus on building strong predictive models that represent the world as it “truly is” in an effort to understand human behavior. For (p. 6) example, we might try to build a model that identifies the mechanisms that predict depressive episodes (i.e., what causes depression). This might have a pragmatic goal underneath it, such as “if we really understand what causes depression, then we can treat and prevent depression.” But the whole approach is about prediction with an assumption that the ability to influence depression will naturally follow.

What is cool about functional contextualism is the idea that we might approach the whole enterprise of understanding human behavior and building up to applied theories with a deep commitment to changing behavior, not just predicting it. The goal is not to model a world as it truly is, but to model a world that gives us the ability to predict and influence behavior reliably. Sometimes those models overlap, but not always. Instead, theoretical concepts and principles ultimately are treated simply as “ways of speaking” that aim to carve up the world in whatever ways aid prediction and influence. An analysis is true insofar as it is useful in telling us how to predict when the behavior will occur and influence the behavior. This allows us to build and discard concepts on the basis of how well they serve these goals—not haphazardly, but in a rigorous way of knowledge building.

For example, the flexible functional approach to ACT is deeply rooted in a pragmatic approach to understanding behavior—whatever works to predict and influence behavior. There is no “right” way to do ACT. Instead, ACT orients to a set of therapeutic processes that reliably predict and influence behavior, and whatever works to move those processes is functionally doing ACT. Similarly, we encourage you to focus on workability with your clients; there is no right or wrong way to live their lives, but we can help them identify what is not working and find what works well, based on what they want for themselves.

Successful working is the goal

This brings in another interesting aspect of functional contextualism, which is the need to state the goal we are working toward so we can evaluate success. In science, we use prediction and influence, but with clients we need more precision in terms of what they are working for. In this way, the values work in ACT really echoes from these functional contextual roots in terms of identifying the criterion for what works with the client and using that as a touchstone to figure out how well things are going in therapy. If a given ACT strategy does not help a client move toward what matters to them, then it does not work and should be discarded to try something new. This is part of what we really like about ACT and what makes us passionate to teach it to others. Ultimately, it puts the client in the driver’s seat to find and build on what is going to work to live a meaningful life in line with what deeply matters to them.

(p. 7) The Behavior Analytic and Cognitive Roots of ACT

ACT is rooted within behavior analysis, and in many ways functional contextualism simply explicates the underlying assumptions and philosophy of at least a primary wing of behavior analysis (Hayes et al., 1988). ACT uses behavior analytic principles and methods, which provide basic analytic units for understanding reliable relations between context and behavior that can be used to predict and influence behavior. This again is reflected in ACT, with an emphasis on understanding behavior in context for assessment, case conceptualization, and intervention. Many of the ACT concepts and methods you will learn are direct or indirect reflections of traditional behavior analysis and its extensions into clinical work.

That said, ACT diverges from traditional behavior analysis in an important area that is also reflected in the divergence that was found when CBT emerged from traditional behavior therapy. During the 1970s, therapists were increasingly becoming disillusioned with the limitations of traditional (first-wave) behavior therapy for problems clients routinely presented with and were embracing cognitive therapy approaches pioneered by leaders such as Aaron Beck, Albert Ellis, and Jack Rachman, which influenced CBT as we know it today. Although behavior analysis included a progressive scientific account of internal experiences including cognitions, pioneered by B. F. Skinner, this behavior analytic account was limited when extended to more complex human phenomena typically encountered in therapeutic work. Thus, just like cognitive therapists who shifted from behavior therapy to CBT because they needed a more comprehensive account of cognition, early ACT development led by Steven Hayes faced a challenge in addressing cognition with the available behavior analytic tools (Zettle, 2005). This led to the development of relational frame theory (RFT; Hayes, Barnes-Holmes, & Roche, 2001), a modern behavior analytic account of cognition that informs approaches like ACT to address the complexities of behavior enacted by verbal animals.

Thus, in some ways, ACT ended up in a similar place as traditional CBT, with a melding of a traditional behavioral approach with more modern accounts of cognition. But the pathway ACT took was different and resulted in a quite distinct foundation and set of analytic tools—defined by functional contextualism and RFT (Hayes et al, 2013).

We will take a moment here to explain RFT a bit to show how this distinct behavior analytic account of cognition has substantial implications for how clinical problems are conceptualized and treated in ACT. The core of RFT is that verbal humans have the ability to relate things to each other—even relations that are not immediately obvious and that have never been learned before—and these relations can alter how these things function or the effect they have on individuals. By “relations” we mean all the ways we might describe how one stimulus is similar to, different from, bigger or smaller than, a part of, contingent on, or otherwise associated with another stimulus. These relations are the “glue” that hold together many complex ideas and rules for behavior that can be adaptive or maladaptive (e.g., (p. 8) “Having one drink is a relapse, and if I relapse then I’m a failure, and if I failed, I might as well keep drinking.”). What makes RFT so innovative and important for ACT is that these ways of relating things have unique features, including (1) we have the ability to derive new relations that have never been learned; (2) coherence (making sense) functions as a reinforcer; (3) changes in functions can occur through derived relations; and (4) these relations and changes in functions are all controlled by context.

The ability to derive new relations

Humans have a unique capacity to relate things in new ways they have never learned before and that may not be immediately obvious. For example, try this right now. How is a toaster similar or different from a dog? It might take a minute because there are no immediate relations you have learned or that are obvious. But given enough time, you could probably derive a relation between the two—they both are essential parts of any good household, they both eat bread if given the chance, one should be on the counter and the other should not, one runs on electricity and the other on treats and love, and so on.

We know from a long series of carefully controlled studies that humans have the ability to derive relations that have never been taught (Hayes et al., 2001). This can work well in some situations, like if you had to figure out how to escape from a dangerous situation you have never been in. Yet, it can also create challenges, like if you thought you had to escape from a situation that is not actually dangerous. Through the process of being able to relate anything to anything else, we have a fantastic ability to evaluate, plan, create, and problem-solve in ways that make our species incredibly successful. However, we also have a fantastic ability to evaluate in unhelpful judgmental ways, to come up with ineffective plans for events that will never occur, to create new ways of making ourselves and others miserable, and to problem-solve things that are either not problems or not solvable. In any moment, we can relate seemingly trivial, neutral things to incredibly aversive, upsetting things, thus greatly expanding our capacity for suffering. For example, we can associate anything with the label “bad,” including our bodies, feelings, and thoughts, and such associations can be unhelpful if we then respond to these stimuli accordingly.

Coherence as a reinforcer

The second key feature identified by RFT is that these relations are reinforced by coherence, meaning we relate things that make sense and seem logical. Again, this is a useful cognitive process because it is usually adaptive to think logically and not contradict ourselves. But this also means relating is automatically reinforced by coherence and thus can continue to elicit and strengthen the ongoing behavior without conscious attention. Much like how eating each chip in a bag of chips (p. 9) can be automatically reinforcing and lead to the next chip, we can keep “making sense of things” all day. This might explain the automatic nature and frequency of thinking. We are constantly relating things to each other, seemingly on autopilot, and without much ability to control it. We do not relate things based primarily on what makes us feel good or helps us but rather what makes sense. Consequently, we can get wrapped up in an ongoing stream of a logical story about how we are not good enough, will never be loved, should give up, and so on. Again, as this process is automatic, ACT uses strategies (mindfulness, acceptance) to observe this process and choose when to be regulated by it.

Changes in function

We might be able to relatively easily manage just these two features of relating anything to anything else on an almost constant loop based on what “makes sense,” if not for a third feature. The ways we relate things change how these things function. If we were constantly evaluating ourselves and thinking about how we are terrible but it did not change how we felt, acted, or otherwise engaged in the world, it probably would not be a big deal. But in actuality, how we relate (or think about) things affects all these other aspects of our functioning. The thought “I can’t handle my anxiety” can transform the discomfort of anxiety into absolute fear as anxiety becomes something dangerous, unmanageable, and to be avoided at all costs. This can not only intensify an event but also change its overall meaning. For example, if being at home on a Friday night is related to “nobody likes me,” then watching a movie and relaxing at home can all of a sudden be a sad and lonely activity, despite its being an enjoyable event without that thought.

This is all contextually controlled

Although we can relate anything to anything and thereby change our experiences and reactions to these things, this process is not random. Rather, all these relations and transformations through relations are governed by context. This is why when you see the letters bat you do not immediately have all the reactions you would normally have to seeing a disgusting, flying rodent (apologies to bat lovers) as well as to playing baseball. Rather, the symbols associated with bat only have meaning in context, such as your history with these symbols, the collection of symbols surrounding it, and the context in which you are interacting with this book. We could say “Get out, there is a fire,” but you probably would not run out the house right this moment because of the context. However, you might do that if someone woke you up at 3 a.m. yelling the exact same phrase. Context is extremely important in governing how we relate things and how things change as a result. This is extremely important for ACT as a functional contextual approach because it gives us a way to reduce maladaptive functions and build up more adaptive ones. For example, we can shift the important and sad thought “I’m fat” to “funny sound (p. 10) that shows up in my head” using techniques like acceptance and mindfulness. We can also tie scary or anxiety-provoking events to something meaningful and alter the functions of those emotions (e.g., approach rather than avoid) using values.

How People Get Stuck: The Psychological Inflexibility Model

Overall, this combination of traditional behavior analysis with the additional insight of RFT provides the principles for developing an applied theoretical model of psychopathology (or a theory for how people get stuck) which we call psychological inflexibility. This model orients to how cognitive processes alter direct behavioral contingencies to produce excessive suffering and a lack of meaningful, effective action. Overall, psychological inflexibility refers to rigid patterns of behavior in which actions are excessively guided by internal experiences (e.g., thoughts, feelings, cravings) rather than direct contingencies (what is effective) and values (what is meaningful). These are most exemplified by two processes: cognitive fusion and experiential avoidance.

Cognitive fusion describes responding to thoughts in a literal context or as if they were absolutely true. A fused response to “You’ll never understand ACT” would be one that treats this as reflecting reality and thus guiding your experiences and behavior. Maybe you will feel sad or anxious and choose to put this book away, never to be opened again. In other words, cognitive fusion means thoughts “push us around” and we do whatever they tell us to do. Similarly, a client who is fused with the thought “There’s no point in trying” might give up on an important goal or activity, like quitting smoking, applying for a new job, and so on. Irrespective of how accurate the thought is, the issue is behavior is dominated by thoughts rather than other sources of information.

Experiential avoidance refers to rigid attempts to avoid, get rid of, control, or otherwise change inner experiences (e.g., thoughts, feelings, bodily sensations). This can take many forms because experiential avoidance is defined by the purpose the behavior is intended to serve (regulate inner experiences), not what the behavior looks like. Someone might engage in experiential avoidance by drinking, withdrawing from others, trying to suppress thoughts, cleaning, exercising, practicing mindfulness, or even seeing a therapist. Essentially, if clients are doing a certain behavior to try to get away from an unwanted thought, feeling, or other inner experience, they are engaging in experiential avoidance no matter how “healthy” the behavior looks.

Interestingly, this means either doing what thoughts tell us to do or focusing on trying to make thoughts and other inner experiences go away are form of psychological inflexibility that leads to suffering. This makes sense, coming back to context because, in both cases, thoughts, feelings, and other inner experiences are being related to in a literal way, either as true rules that must be followed or as bad, dangerous things that must be avoided. ACT takes the stance that psychological problems are not due to our inner experiences being bad things that must (p. 11) be changed. Rather, many of our problems may be due to how we relate to our experiences, and, more specifically, relating to our experiences as bad, maladaptive things that must be changed may be part of the problem—not the solution.

Acceptance and Mindfulness as a Pathway to Reduce the Impact of Inner Experiences

Based on the psychological inflexibility model, clients get stuck when their actions are dominated by their inner experiences and reflect efforts to avoid these experiences. Thus, a large part of ACT is reducing the functional impact of inner experiences by changing how we relate or respond to them. This differs from the default way we typically relate to and try to address inner experiences.

ACT addresses inner experiences through the use of acceptance and mindfulness-based therapeutic procedures. Rather than changing the content of inner experiences, the aim of ACT is to change our relationship to these inner experiences so that they have a weaker impact on behavior. For example, ACT might teach a client to relate to the thought “Everyone thinks I’m weird” as just a thought and to make room for the discomfort of approaching social situations even when difficult thoughts and feelings arise. Rather than inner experiences, ACT targets engagement in meaningful and effective behaviors while being mindful and accepting of inner experiences that arise. When we take this stance, the thought “Everyone thinks I’m weird” does not have to change, because it no longer affects what we do. That is, we can still go to social gatherings and ask people out with the thought “Everyone think I’m weird” present because we have learned to relate to it as just a thought rather than something literally true that must be acted on, fought with, or otherwise treated as a real thing. We typically break these methods down into four core components: cognitive defusion, acceptance, being present, and a flexible sense of self (or self-as-context).

Cognitive defusion is the process of noticing thoughts as just thoughts. It most directly targets its inverse, cognitive fusion. Going back to RFT, this is all about changing the context in which we are responding to inner experiences, such as thoughts. Cognitive defusion helps shift from a literal context where thoughts are true and have power and meaning to one in which thoughts are noticed as just thoughts. For example, we might help a client see a thought as just a bunch of funny symbols on a piece of paper, arbitrary sounds when said out loud, history of which they can recall past occurrences, as a character from a favorite TV show, or even an overeager assistant trying to do its best to help out. The idea is to emphasize other ways our mind works besides the specific one we typically operate on, which is the literal content of what a thought is saying.

Acceptance involves being open and welcoming to unwanted thoughts and feelings and allowing them to be present for what they are without giving into or trying to make them go away. This most directly targets its inverse, experiential avoidance. Initially, acceptance might seem to just be the act of not engaging in experiential avoidance: allowing these inner experiences to come and go without (p. 12) efforts to avoid or change them. However, this would miss the more active ways in which acceptance is practiced. Acceptance is more than a lack of fighting; it is an intentional, active, and open stance. That is, we choose to make space for difficult thoughts and feelings rather than feel resigned to their occurrence. Acceptance is more akin to graciously receiving a gift from a loved one than to being hit in the face by an unruly wave.

This is predicated on clients’ recognizing these experiences for what they are, thereby creating a context in which thoughts and feelings can be treated as natural reactions instead of things to be avoided or acted on. We emphasize the welcoming stance in acceptance, partly to avoid misinterpreting acceptance as a “just do it” stance where clients are supposed to white-knuckle their way through previously avoided situations while trying to ignore unwanted thoughts and feelings. This can work for a short period, but you would not be doing something radically different with your inner world, and it typically does not work over time as resources and motivation for the effort it takes dwindle. Instead, acceptance means an active, welcoming, mindful approach to inner experiences.

Being present refers to being attentive to relevant experiences and information in the moment in a flexible, effective way. An aspect of psychological inflexibility is the tendency to get stuck with attention rigidly focused on the past or future (e.g., regrets, worries) or to be overly fixated or hypervigilant toward a limited set of experiences in the present (e.g., changes in heart rate, potentially disapproving expressions from others). The aim of ACT is to help clients attend to what is happening in the here-and-now so that behavior can be sensitive to and guided by their current environment—both internal and external. This is another way of reducing the impact of thoughts and feelings as clients attend to a variety of sources of information rather than just their inner world. For example, being present could help a client break out of a mindless eating pattern so they can savor food they enjoy and notice signals that they are full, rather than continuing to overeat on autopilot while they think about their stressors.

Flexible sense of self refers to a process in which clients learn to take a perspective in which the “self” is more than, distinct from, and the container of their inner experiences (a process we also sometimes call self-as-context in ACT). Due to the inherently abstract nature of this process, it is often best understood through experiential exercises and metaphors. For example, imagine you are the sky and your thoughts and feelings are the passing clouds and weather. In other words, you are a stable, broad perspective that can simply observe the passing inner experiences. Just like how the sky cannot be defined by or threatened by the weather, you cannot be defined by or threatened by your thoughts and feelings. This observing self-perspective can help break unhelpful patterns when clients are overly entangled with a “self-story” about who they are, what they should do, what is wrong with them, and so on because the “self” becomes no longer tied to these narratives. Instead, the “self” is perceived as a dispassionate, observing entity through which thoughts and feelings occur. This self-perspective can also strengthen other acceptance and mindfulness processes. It becomes easier to (p. 13) acknowledge and allow experiences to be present for what they are when we can see them as a part of ourselves, rather than as who we are.

The combination of cognitive defusion, acceptance, being present, and a flexible sense of self can be conceptualized as the mindfulness components of ACT. These processes overlap in many ways with conceptualizations of mindfulness as a way of attending to the present in a nonreactive, accepting way. One of the things we like about the ACT approach to these mindfulness processes is that it orients to functional processes that you can engage in various ways with clients outside of typical mindfulness meditation strategies. For example, you can elicit, model, and reinforce these processes in conversations with your client. If a client said in session, “I’m really anxious about this upcoming family party,” a therapist could give a response supporting defusion (“So your mind is saying this could go really bad and is giving many thoughts about what might go wrong.”), or acceptance (“So anxiety is present right now, can we just make space for that to be here?”), or being present (“What are you noticing right now as this anxiety comes up?”), or a flexible sense of self (“Imagine you were at the party right now. What other experiences might you notice passing by like clouds from that ‘sky’ perspective we discussed?”). Echoing back to the pragmatic goal of whatever works to predict and influence behavior, these therapeutic processes can orient therapists to multiple approaches to change client behavior and provide considerable flexibility in how these goals are achieved.

Although these processes largely have the aim of changing the context in which we relate to our thoughts and feelings, they ultimately are used to seek to change what clients do so they are better able to engage in meaningful actions. The goal is not to notice or accept painful psychological experiences for their own sake; it is to empower clients to do what matters even when difficult thoughts and feelings arise. Thus, this work should not end with clients simply doing something “between their ears” but with changing overt behavior. If these mindfulness methods work, we should see changes in behavior. As maladaptive effects of inner experiences on behavior are lessened, clients will have more opportunity to act on the basis of what would be meaningful or effective in the moment.

Values and Committed Action as a Pathway to Doing What Matters

Again, the ultimate goal of ACT is not to change unwanted inner experiences; it is to empower clients to live fulfilling lives. That is, the aim of ACT is to help clients do what matters to them. Thus, lessening the impact of inner experiences on clients’ actions is done in the service of helping clients identify and engage in meaningful activities. As unhelpful guides for action are reduced (e.g., cognitive fusion, experiential avoidance), clients often need help figuring out what they want to be doing and how to actually do it. This is addressed with the values and committed action components of ACT.

(p. 14) Values refers to what is deeply important to clients in terms of how they act and what their actions stand for. We all have things that are important to us and that we would work toward. Sometimes we develop these values individually, and sometimes they are largely culturally based. Regardless of their sources, they function as reinforcers. One way to clarify this is to consider an ordinary action like cooking. You can approach cooking in various ways. For example, you could cook in a way that is creative, fun, connected with other people, giving a sense of purpose and meaning to the activity. However, you could also cook in a way that is mindless, rushed, or resentful. Depending on your stance toward the task, your experience of the same action will likely differ. Thus, actively connecting with our values in the moment can change how we experience our behaviors, making them more fulfilling to us. In other words, values are found in how actions are taken, focusing on the qualities people bring to actions rather than the outcome (whether the meal is delicious or others like it). This is a cognitive process in that clients are asked to describe more abstract principles that can guide and motivate their actions across a range of situations. This is an example of how ACT uses RFT to clients’ advantage: by using cognitions—or our verbal ability to associate anything with anything—to increase effective patterns of behavior and reduce unhelpful effects of cognition on behavior. As you will see in later chapters, ACT uses various strategies to help clients identify their values and learn how to use these values to motivate doing what matters to them.

Committed action refers to the doing part of this work, helping clients build larger and larger patterns of meaningful activity in their lives. In many ways, this is where the “rubber meets the road” with everything done in ACT as clients practice acceptance and mindfulness to move toward their values with specific behavioral commitments. This might fit in well with other behavior change work you have done in which you set specific goals with your clients for what they will do to make meaningful changes and practice what they have learned in therapy. Committed action includes goal setting and sometimes behavioral methods that help ensure that clients are successful in following through with their goal (e.g., behavioral activation, exposure). Committed action is also where other behavioral methods might be integrated to teach clients how to do new things if there is a skills deficit (e.g., social skills training). Lastly, we use committed action as a way to orient to ongoing therapy goals and relapse prevention from an ACT perspective focusing on building patterns of valued activity over time and returning to commitments when clients go off course.

This All Leads to Psychological Flexibility

Altogether, this combination of acceptance, mindfulness, and values-based processes is referred to as the psychological flexibility model, which is the ACT model for psychological health and therapeutic change. Thus, psychological flexibility refers to the ability to engage in meaningful actions while being mindful and accepting of whatever inner experiences arise—in other words, to be able to (p. 15) do what matters while being open and aware to whatever the present moment affords, including unwanted thoughts and feelings. The hexaflex graphic is commonly used to display this model (see Figure 1.1), which highlights how each of the processes we have discussed are part of psychological flexibility and interconnected. For example, being able to notice thoughts as just thoughts (cognitive defusion) is predicated on attending to thoughts (being present), which can then help facilitate accepting difficult thoughts (acceptance) and doing what matters (values, committed actions). Overall, psychological flexibility is the solution to getting stuck in psychological inflexibility.

Figure 1.1 A model of psychological flexibility and its subprocesses.

Figure 1.1 A model of psychological flexibility and its subprocesses.

This psychological flexibility model provides a guide for how to conceptualize cases and practice ACT with your clients. For example, some clients may struggle more with targets on the left side of the hexaflex, by being caught up in thoughts or being avoidant, while others might struggle more with the right side, by not knowing what matters to them or not knowing skills deficits in being able to act effectively. Similarly, you might notice different processes at play in any moment (e.g., a client being on autopilot and disconnected with values) and points at (p. 16) which you will have to choose what process to leverage (e.g., should I lean in on attending to the present moment or explore their values?).

The psychological flexibility model orients back to where we started in this chapter: ACT is defined functionally in terms of a set of therapeutic processes designed to help clients get unstuck from patterns that prevent them from doing what matters in their lives. Psychological inflexibility can manifest differently across individuals. Hence, the focus is on the function of behaviors (i.e., actions that are overly guided by literal interpretations of thoughts or avoiding unwanted inner experiences). These functions can underlie a wide range of clinical presentations and problem behaviors with which you might work—wherever people can get stuck in unhelpful ways of relating to their inner experiences. This also means ACT can be applied across this breadth of clinical presentations to reduce psychological inflexibility by increasing psychological flexibility.

Applying the Psychological Flexibility Model: Doing ACT

A focus on function over form not only expands the variety of clients to whom ACT can be applied, it also expands the variety of ways a therapist can increase psychological flexibility. ACT is not defined by any technique or specific form of behavior on the part of the therapist; what matters is that the therapist has a functional impact on their client that increases psychological flexibility. This means you can fit ACT to your personal style, skills, and setting, taking your existing strengths and applying them to the psychological flexibility model.

That said, this can also be a challenge for therapists new to ACT. There are countless ways to implement ACT with your clients, and trainings in ACT regularly focus more on the function and flexibility with which ACT can be implemented. This can sometimes make it hard for therapists learning ACT to know what to do in the moment with clients, how to stick to ACT rather than fall back into other treatments they already know, and how to build on areas in which they have less competence.

In this book, we will focus on one way to do ACT. That is all it is: one way among many to use the psychological flexibility model. We hope to provide a set of stepping stones you can use to begin your journey with learning ACT. You can follow the protocol in this book for an initial set of cases, using the structure and scaffolding to learn the basics. As you practice this protocol, you will hopefully get a better sense of what it looks like to do ACT in the moment, how to identify the target functions in ACT in session, and some key ACT strategies. We hope this gives you a basic foundation you can build on and integrate into your therapeutic style and orientation as you continue to explore the exciting and broad opportunities that ACT provides in working with clients to make meaningful changes in their lives.


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