To address the problem of recruiting physicians to deliver smoking cessation interventions, Doctors Helping Smokers included a trial of physician recruitment strategies. In round 1 of Doctors Helping Smokers, three types of informational materials were mailed directly to 110 family physicians. The physicians were asked to return a postcard if they were interested in participating in a 1-month trial of a smoking cessation intervention. Response did not differ among the three conditions; overall, 9.8% of physicians (95% confidence limits [CL], 8.0, 11.6) responded and 6.05 (95% CL, 4.6, 7.4) eventually participated in the intervention trial. The same procedure was repeated for round 2 of Doctors Helping Smokers with direct mailing to all general internists and cardiologists (n = 1108) on the mailing list of the Minnesota Medical Association. Five percent (95% CL, 3.7, 6.3) of the internists responded and 2.7% (95% CL, 1.7, 3.7) participated in the trial. Recruitment for round 3 mnade use of repeated face-to-face recruitment efforts at the physician's office through a managed-care organization that held contracts with the physician's clinic to provide care for its enrollees. Six months after the initiation of round 3, 59% (95% CL, 49%, 67%) of the 126 primary care physicians reported that they were giving their patients smoking cessation advice and completing the smoking intervention records. Eighteen months after the initiation of round 3, 56% (95% CL, 47%, 65%) of the 116 primary care physicians who remained in the practice reported continued activity in the project.