Some of the most significant advancements in the treatment of Tourette Syndrome (TS) over the past 40 years have been made using behavior therapy. This presentation will review investigations initiated in 1985 consisting of a series of single-participant research design studies to develop and evaluate Habit Reversal Therapy for TS. The presentation will then review a series of additional clinical trials that led to the development of the Comprehensive Behavioral Intervention for Tics (CBIT). The results of these 40 years of clinical trials have resulted in CBIT being listed as one of the most effective treatments for TS in international clinical practice guidelines. In addition, with the support of the TAA, CBIT has been one of the most successful examples in history of the dissemination and implementation of an evidence-based behavioral treatment to world-wide clinicians and patients.