To identify strategies likely to improve composite measures of diabetes care quality. Methods: Study subjects were 14,750 adults with diabetes identified in one care delivery system in the SUPREME-DM project (HS19859) who had BP measures in both 2005 (Y1) and 2010 (Y2). We report the proportion of patients who met clinical goals (A1c <8%, LDL <100 mg/dl, BP<140/90, no tobacco use, or composite D4 goal requiring all 4 components to be at goal) in Y1 but not in Y2, based on the last available assessments in each of the two 12-month periods. Results: Among those with measures in Y1 and Y2 and at goal in Y1, the proportion not at goal in Y2 for A1c, BP, LDL, tobacco, and the D4 was 13.7%, 8.5%, 12.8%, 1.6%, and 20.7% respectively. When those missing measures in Y2 were classified as not at goal in Y2, the proportion of those in control in Y1 but not in Y2 for A1c, BP, LDL, tobacco, and the D4 was 25.7%, 8.5%, 27.1%, 24.1%, and 52.6% respectively. Among those with measures in both Y1 and Y2, the proportion of all those not at goal in year 2 who had been at goal in Y1 for A1c, BP, LDL, tobacco and the D4 was 21.1%, 45.2%, 25.9%, 14.1%, and 14.7% respectively. The proportion of those who failed to meet the D4 goal because of missing measures of one or more D4 components was 52.2% in Y1 and 54.1% in Y2. Conclusions: Strategies to improve composite measures of diabetes quality include: (a) Record measures of A1c, LDL, and tobacco use more frequently, and (b) Implement strategies to prevent clinical relapse in those at highest risk of relapse, especially for BP.