This article discusses the foundational principles, basic concepts, and methods of cognitive behavioral therapy (CBT) for obsessive-compulsive disorder (OCD). It covers the interconnection between thoughts, feelings, and physical sensations, the importance of a sound therapeutic alliance, the focus on collaboration and active participation, and the goal-oriented and present-focused nature of CBT. The article also delves into the basic techniques involved in CBT, such as cognitive rehearsal, validity testing, modeling, and homework. Finally, it presents the results of a clinical trial that evaluated the efficacy of CBT in treating OCD.