We examined the relationship between physician adherence with a smoking cessation guideline and organizational structures, policies, leadership support, and physician knowledge and attitudes. A random sample of 844 physicians practicing in 127 VHA hospitals was surveyed. Survey results were aggregated to the hospital level and linked with data on organizational characteristics from the 1998 annual survey of hospitals by the American Hospital Association. Significant predictors of adherence included organizational policies related to nicotine replacement prescriptions, the timing and effectiveness of guideline implementation, physicians' knowledge of VHA clinical guidelines generally, and physicians' beliefs about the receptiveness of patients to smoking cessation.