OBJECTIVE: To describe the occurrence of common medical and psychological conditions in individuals with Down syndrome during their life span, and to measure the use of the Down Syndrome Medical Interest Group's health care guidelines by family physicians across Canada, as reported by parents or caregivers. METHODS: The Down Syndrome Research Foundation sent a questionnaire to 314 families across Canada who were part of the Canadian Voluntary Registry on Down Syndrome. This questionnaire was designed to collect information front parents about physical examinations, laboratory tests, referrals and discussions with family physicians that are listed in the health care guidelines. RESULTS: Two hundred twenty-three families responded to the Survey. The highest response rates were in families with children in the five- to 12-year-old age range (41.7%) and the 13- to 18-year,old age range (19.7%). The most common medical conditions reported were Visual, hearing and cardiac related. A high percentage of sleep, gastrointestinal and thyroid-related conditions were also reported. In the adult group (ie, 30 years of age and older), there was a high proportion of depression and/or anxiety disorders reported. The percentage of those reporting physical examinations and medical referrals by family physicians were highest in the five- to 12-year-old age range and dropped below 50% in those aged 19 years and older. In the One- to four-year-old and five- to 12-year-old age groups, the percentages of those with Down syndrome referred for hearing tests and celiac screens were reported to be below 30%. The percentages of those reporting discussions on behavioural issues were below 50% in all age groups. CONCLUSIONS: Physical examinations, as per the recommended guidelines, were followed only in the five- to 12,year-old age group. Many of the recommendations regarding discussion of behavioural problems, transition planning, diet, exercise and issues around puberty Or Sexual health were followed infrequently in all age groups. Further physician education about the guidelines is necessary.