The discovery and use of insulin revolutionized diabetes treatment and improved life for people with diabetes, especially those with type 1 diabetes. Nearly 95 years later, insulin remains the mainstay of treatment for type 1 diabetes and gestational diabetes mellitus and is also used for many people with type 2 diabetes. The evolution of insulin has continued through the years. There are now more than 15 insulin products in the U.S. market, with more in the pipeline. In the past century, new formations and delivery systems have become available that have improved the pharmacokinetics, pharmacodynamics, and ease of use of insulin for patients. In a recent article in Diabetes Care, Cefalu et al.