This online therapist guide presents a comprehensive program for assessing and treating sexual dysfunction in couples or single individuals, regardless of sexual orientation. It outlines pathways for therapy and gives recommendations for formulating a treatment plan. Therapists are encouraged to be flexible in their approach while guiding clients through this step-by-step program. Alongside the corresponding online workbook, it presents information on a number of sexual problems including low sexual desire, difficulty becoming sexually aroused, premature or quick ejaculation, erectile dysfunction, trouble achieving orgasm, and pain or discomfort during sex. Clients are educated about sexual development and common sexual myths, as well as factors that influence sexual functioning in order to create favorable conditions for sex. For each topic, this online guide offers an overview of principles underlying treatment and main concepts to convey to clients. Case vignettes illustrate key points and important tips for the therapist are highlighted throughout.