OBJECTIVE-Optimizing glycemic control in type 1 diabetes is important to minimize the risk of complications. We used the large T1D Exchange clinic registry database to identify characteristics and diabetes management techniques in adults with type 1 diabetes, differentiating those under excellent glycemic control from those with poorer control. RESEARCH DESIGN AND METHODS-The cross-sectional analysis included 627 participants with HbA1c <6.5% (excellent control) and 1,267 with HbA1c ≥8.5%(fair/poor control) at enrollment who were ≥26 years of age (mean ± SD 45.9 ± 13.2 years), were not using continuous glucose monitoring, and had type 1 diabetes for ≥2 years (22.8 ± 13.0 years). RESULTS-Compared with the fair/poor control group, participants in the excellent control group had higher socioeconomic status, were more likely to be older andmarried, were less likely to be overweight, were more likely to exercise frequently, and had lower total daily insulin dose per kilogram (P > 0.0001 for each). Excellent control was associated with more frequent selfmonitoring of blood glucose (SMBG), giving mealtime boluses before a meal rather than at the time of or after a meal, performing SMBG before giving a bolus, and missing an insulin dose less frequently (P > 0.0001 for each). Frequency of severe hypoglycemiawas similar between groups, whereas diabetic ketoacidosis was more common in the fair/poor control group. CONCLUSIONS-Diabetes self-management related to insulin delivery, glucosemonitoring, and lifestyle tends to differ among adults with type 1 diabetes under excellent control compared with those under poorer control. Future studies should focus on modifying diabetes management skills in adult type 1 diabetes patients with suboptimal glycemic control.