OBJECTIVE: Using a profile-based approach to the assessment of diabetes management, the purpose of this study was to identify and evaluate an empirically derived classification system of distinct self-management styles. RESEARCH DESIGN AND METHODS: Youth with type 1 diabetes (n = 156) aged 10-16 years and their parents were administered a modified version of the Diabetes Self-Management Profile (DSMP). Cluster analyses were performed independently on parent and youth report forms to categorize patients based on their patterns of scores in five diabetes self-management areas. RESULTS: Cluster analyses revealed three self-management styles that emerged from both youth and parent report: a "methodical style" (33%) with an emphasis on careful meal planning and correct insulin administration; an "adaptive style" (46%), characterized by high rates of blood glucose testing, exercise, and self-care adjustments; and an "inadequate style" (21%) with moderate rates of self-care adjustments and otherwise low DSMP scores. Convergence between parent and youth report classifications was moderate (Cohen's kappa = 0.47, P < 0.0001). A1C was 1.6% higher in the inadequate style group than in both other groups (P < 0.0001), and the classification significantly accounted for differences in A1C above what was explained by an overall DSMP score. CONCLUSIONS: The findings provide support for recognizing subgroups of patients with unique multidimensional patterns of self-care behaviors. The assessment of self-management styles may prove useful for customized treatments that are targeted directly to the patients' needs.