Recruitment will occur by phone or in the clinic by the Practice Based Research Network (PBRN) using the attached screener. Prior to contact, patients will have been identified as potentially eligible by having had a current or past diagnosis of depression as indicated in the Regenstrief Medical Records System. These potentially eligible persons must then be approved for the study and moderate-intensity exercise by their primary care provider before the recruitment call and screener from the PBRN. The telephone screener uses the PHQ 9 (Patient Health Questionnaire-9) and a modified Stanford Brief Physical Activity Scale. Those with a PHQ-9 score of 10 or greater and who indicate no current regular physical activity will be eligible for further screening.