Purpose. The relationship between hospitals' organizational characteristics and adoption of restrictive smoking policies was examined. Design. Self-administered questionnaires and telephone interviews were conducted prior to and following the target date for policy implementation. Setting. The Director of Regional Medical Services of a community network of hospitals requested in the summer of 1989 that the 57 member hospitals voluntarily implement a policy prohibiting all smoking in hospital buildings as of January 1, 1990. Subjects. Subjects were the 49 hospital CEOs (86%) who provided data at both time points. Intervention. The Director of Regional Medical Services made a personal request of the CEO during a routine visit at each hospital. Measures. Measures included structural aspects of the hospitals (e.g., number of employees, number of beds, presence of chemical dependency and psychiatric units); orientation toward employee health; support for smoking restrictions among various groups; and extent of CEO authority to set smoking policy. Results. Fifty-one percent of hospitals increased the restrictiveness of their smoking policy; 35% adopted a complete indoor smoking ban. Stepwise multiple regression analysis demonstrated that adoption of additional smoking restrictions was related to CEOs' and perceived board of directors' support of smoking restrictions, absence of a chemical dependency unit, and experience of financial difficulties in the previous two years. Conclusions. It is important to educate top decision makers as to the necessity of restrictive smoking policies. Barriers to smoking restrictions in organizations with chemical dependency units deserve particular attention from health promotion practitioners and researchers.