A random-digit dialing telephone survey was conducted in the second half of 1991 to examine parental attitudes toward legislation of helmet use by child cyclists. The surveyed population were 703 parents of at least one child aged 5-17 years who owned a bicycle and lived within Metropolitan Toronto. Five hundred sixty-eight (80.8%) responding parents were in favour of the suggested legislation, 81 (11.5%) were against, and 54 (7.7%) had no opinion on the issue. The 95% confidence interval for the support rate was 78.9-83.7%. Although there was some variation in the level of support, at least two thirds of the respondents in every subgroup, except parents with teenaged children (aged 15-17 years), were in favour of the legislation. Legislation requiring bicycle helmet use by all children has strong support from the public. Additional surveys should be directed at public attitudes to legislation of helmet use by adults.