Long-acting insulins have been developed for patients with diabetes to provide a basal insulin cover during the day and night. The first slow-release formulations used protamine and/or zinc to achieve a duration of action up to 16 hours. Since 2000 insulin analogues with different mechanisms of protraction are available and achieve a predictable glucose lowering effect with one daily injection. Currently, ultra-long acting insulin analogues are available that have a duration of action beyond 24 hours. This prolonged duration of action reduces day-to-day variability and offers daily dosing flexibility . What further improvements in basal insulin therapy can be expected in the future and what exactly does the ideal basal insulin look like?