C-peptide, historically considered a biologically inactive peptide, has been shown to exert insulin-independent biological effects on a number of cells proving itself as a bioactive peptide with anti-inflammatory properties. Type 1 diabetic patients typically lack C-peptide, and are at increased risk of developing both micro- and macrovascular complications, which account for significant morbidity and mortality in this population. Inflammatory mechanisms play a pivotal role in vascular disease. Inflammation and hyperglycemia are major components in the development of vascular dysfunction in type 1 diabetes. The anti-inflammatory properties of Cpeptide discovered to date are at the level of the vascular endothelium, and vascular smooth muscle cells exposed to a variety of insults. Additionally, C-peptide has shown antiinflammatory properties in models of endotoxic shock and type 1 diabetes-associated encephalopathy. Given the antiinflammatory properties of C-peptide, one may speculate dual hormone replacement therapy with both insulin and Cpeptide in patients with type 1 diabetes may be warranted in the future to decrease morbidity and mortality in this population.