To assess Ontario family physicians' attitudes toward, awareness of, and practices related to self-help groups in general and cancer self-help groups specifically.Mailed survey using a modified Dillman method.Ontario family practices.A random sample of 1500 Ontario members of the College of Family Physicians of Canada, of whom 949 responded. A total of 911 completed questionnaires were received, for an eligible response rate of 64%.Physician demographics, practice characteristics; extent of awareness of self-help groups and their perceived value; attitudes toward self-help groups; practices related to interactions with patients about self-help groups.Only 40.2% of respondents were aware of six or more self-help groups in their region; 56.8% were aware of at least one cancer self-help group. Discussions with patients about groups were reported as occurring "frequently" by 12% of respondents, who indicated they made referrals to an array of groups. Ratings of group helpfulness were relatively high (83.8% scoring 3, 4, or 5 on a 5-point scale, where 5 is "very helpful"). There were low ratings of potential harm (1% scoring 4 or 5 on a 5-point scale, where 5 is "very harmful"). Confidence intervals for proportions reported on in this paper were all within 4%.Family physicians have predominantly positive attitudes about the potential benefits of self-help groups, and many are recommending groups to their patients.