The Sequenced Treatment Alternatives to Relieve Depression (STAR*D) project will provide symptomatic and functional outcome data to evaluate the theoretical principles and clinical beliefs that currently guide the treatment of nonpsychotic major depression. Cognitive Therapy (CT) for depression has been chosen as a switch or augmentation treatment for patients who have failed an adequate trial of the antidepressant citalopram. We describe the rationale, organization, and role of CT in STAR*D. We discuss the issues involved in developing and implementing CT in a large, multisite, effectiveness study: therapist selection, training, certification, quality assurance, and post-training supervision. We conclude with a discussion of the implications of our implementation procedures on interpreting the results of the STAR*D study.