Purpose of Review The goal of this review is to provide updates on the safety and efficacy of long-term sulfonylurea use in patients with KCNJ11 -related diabetes. Publications from 2004 to the present were reviewed with an emphasis on literature since 2014. Recent Findings Sulfonylureas, often taken at high doses, have now been utilized effectively in KCNJ11 patients for over 10 years. Mild–moderate hypoglycemia can occur, but in two studies with a combined 975 patient-years on sulfonylureas, no severe hypoglycemic events were reported. Improvements in neurodevelopment and motor function after transition to sulfonylureas continue to be described. Summary Sulfonylureas continue to be an effective, sustainable, and safe treatment for KCNJ11 -related diabetes. Ongoing follow-up of patients in research registries will allow for deeper understanding of the facilitators and barriers to long-term sustainability. Further understanding of the effect of sulfonylurea on long-term neurodevelopmental outcomes, and the potential for adjunctive therapies, is needed.