The aim of this study was to investigate the current status of smoking policies in Scottish schools, and the relationship between policy status, enforcement of smoking restrictions and perceptions of smoking behaviour among pupils and teachers. A representative sample of 15-year-old school pupils from 77 Scottish secondary schools was surveyed in 1998 regarding their perceptions of smoking in several locations within and outside the school building. Two staff members from each school were also surveyed regarding school smoking policies for pupils and teachers, the nature of the school's smoking restrictions, and the extent to which the restrictions were enforced. The results showed that more schools had a written policy on teacher smoking than on pupil smoking. All schools in the sample banned smoking by pupils, but the majority allowed smoking by teachers in restricted areas. Irrespective of the type of policy or restrictions on smoking, pupils reported seeing smoking among both pupils and teachers on school premises in all of the sample schools. Whether or not a school had a written policy appeared to be unrelated to pupil smoking in the toilets or teacher smoking outdoors on school premises. However, pupils were less likely to be aware of pupils smoking outdoors and teachers smoking in the staff rooms in schools where there were written policies on pupil and teacher smoking, respectively. Consistent enforcement of a ban on pupil smoking was associated with lower levels of perceived smoking among pupils. Where a complete ban on teacher smoking existed, smoking among teachers was seen less often in the staff rooms, but more often in outside areas on school premises. The results have implications for the use of policy in promoting a healthy school environment.