Attitudes of physicians toward counseling patients about their smoking habits may influence whether and how counseling occurs. In this paper, the authors develop and test a conceptual model of these attitudes. The model includes four attitude dimensions: physicians' motivations to counsel, perceived health risk of smoking, perceived skills in counseling, and perceived costs and benefits to the physician of counseling. A self-report questionnaire including a 40-item measure of these attitudes was delivered to a random sample of male general practitioners, internists, surgeons, and obstetrician-gynecologists who were members of a western county medical society in 1978. The response rate was 76%. Based on factor analyses, 10 subscales and 3 global scales were formed by summing items. The item contents of scales are consistent with the authors' model, and reliability and item-discriminant validity are excellent. The authors' model may be useful in understanding the factors that affect the process and outcomes of physician counseling about smoking.