Provided herein are stapled or stitched polypeptides comprising an alpha-helical segment, wherein the polypeptide binds to the insulin receptor, and wherein the peptide comprises at least two cross-linked amino acids as shown in Formula (iii), or at least three cross-linked amino acids as shown in Formula (iv). Further provided are pharmaceutical compositions comprising the stapled or stitched polypeptides, methods of use, e.g., methods of treating a diabetic condition or complications thereof. Precursor “unstapled” polypeptides useful in the preparation of stapled and stitched polypeptides are also described.