Résumé : Little is known about the impact of smoking policy on companies' policies related to smoking in Belgium. The study was designed in order to compare the companies' policies related to smoking (CPRS) in 1990 and in 1993. During this 3 year period, numerous information and regulation inputs (media, brochures) were aimed at companies to regulate smoking behavior in the workplace, so as to reduce the risks of passive smoking. A short questionnaire was mailed to 3543 Belgian companies in October 1990 and in June 1993 to assess: designation of smoke free areas (SFA); willingness to offer a worksite information program (WIP); willingness to offer a worksite smoking cessation program (WSCP); willingness to subsidize a WSCP; willingness to offer a WSCP during working hours; willingness to offer a meeting room for a WSCP and actual organization of a WSCP. In 1990, 773 companies (22%) and in 1993, 890 companies (25%) responded to the questionnaire. The results showed that small companies and companies with a high blue/white collar ratio were less able to implement health policy recommendations. A total of 325 (9%) companies responded to the 1990 and 1993 questionnaires. Comparison of 1990 and 1993 dataset showed that during this 3 year period, no major changes occurred for a majority of companies. Amongst the small positive changes, only the designation of smoke free areas and the organization of a small number of WSCP was observed. The conclusion is that despite inputs, little impact on smoking policies is noticeable. Strategies designed to intensify inputs and to promote implementation of regulation of WSCP should therefore further be studied. © 1997 John Wiley & Sons, Ltd.