This study estimates the effects of place on the distribution of health problems, health-related quality of life, general well-being, and family functioning for youths and adults aged 12 years and older. Data come from the Ontario Health Survey, a cross-sectional study done in 1990 to provide baseline statistical data on population health within 42 public health units throughout the province. Place effects were generally small and were influenced by both the size of the geographic area used to define place and the health indicator selected for study. Variations in health explainable at the public health region level were less than 1%. Variations in health explainable within smaller geographic boundaries (enumeration areas) ranged from 4.7% for health problems to 0.2% for family functioning. Adjustment for area differences in the age, gender, education, marital status, income, and birthplace of inhabitants reduced these place effects at the enumeration area level to 3.7% for health problems and to less than 0.1% for family functioning. The lack of evidence for place effects within large jurisdictional boundaries raises questions about both the usefulness of carrying out health needs assessment surveys within these areas and the informativeness of these geographic boundaries for studying place effects.