Depression in primary care: learning lessons in a national quality improvement program.

In this introduction, we describe the overall context and rationale for the Depression in Primary Care program and the design and implementation of its key components, especially emphasizing its unique combined clinical and economic/systems framework. We also discuss some of the new challenges and opportunities that may impact the program's evolution and the state of behavioral health care more generally. We conclude with some thoughts on potential future scenarios and strategies for improving the quality of behavioral health care, including the treatment of depression in primary care.