OBJECTIVE: To determine the extent to which patients' awareness, treatment, and control of hypertension and hypercholesterolemia have changed over time and to examine factors associated with awareness and treatment in a type 1 diabetes population. RESEARCH DESIGN AND METHODS: Data from six examinations conducted over 10 years from the Pittsburgh Epidemiology of Diabetes Complications Study, a prospective study of subjects with childhood-onset (<17 years of age) type 1 diabetes diagnosed between 1950 and 1980 and followed since 1986, were analyzed. Hypertension and hypercholesterolemia were defined according to the concurrent Joint National Committee and National Cholesterol Education Program Adult Treatment Panel criteria, respectively. RESULTS: Results demonstrated that awareness of both conditions has improved; however, control is not optimal (e.g., only 32.1 and 28% of those with hypertension in 1986-1988 and 1996-1998 were controlled, while for hypercholesterolemia, the rates were 0 and 5.5%, respectively). Stratified by age-group (18-29, 30-39, and >40 years), the youngest subjects with hypercholesterolemia were least likely to be treated and controlled to goal levels. Older age and physician contact were correlates of awareness and treatment of hypertension at baseline, while presence of renal or coronary complications was also associated with awareness and treatment of both hypertension and hypercholesterolemia at the 10-year follow-up. CONCLUSIONS: There is a considerable treatment gap, particularly for hypercholesterolemia. Improved treatment of both hypertension and hypercholesterolemia are clearly needed, particularly hypercholesterolemia in younger age-groups who have not yet experienced long-term complications.