Over the past 40 years, new types of insulins have been marketed to mirror the effect of endogenous insulin. With the existing long-acting insulin product patents expiring and the FDA approval of new biosimilar and innovator insulins, adults with diabetes and their physicians will have additional therapeutic options. This observational study will describe the patient characteristics of new and existing users of long-acting or intermediate acting insulins with and without oral anti-diabetic agents (OAD) as well as acute hypoglycemic episodes, acute cardiac events, and A1C measures. The Biologic and Biosimilars Collective Intelligence Consortium (BBCIC) will use the findings from this descriptive analysis to design a comparative study evaluating the real-world effectiveness and safety of biosimilar and innovator insulins.