Peptide-amphiphiles with collagen-model head groups and dialkyl chain tails have been synthesized and shown to self-assemble into highly ordered polyPro II like triple-helical structures when dissolved in aqueous subphases. Evidence for this self-assembly process has been obtained from (a) compression of stable peptide-amphiphile monolayers to molecular areas comparable with triple-helical areas, (b) circular dichroism spectra and melting curves characteristic of triple-helices, and (c) two-dimensional NMR spectra indicative of stable triple-helical structure at low temperatures and melted triple-helices at high temperatures. The thermal stability of the collagen-like structure in the peptide-amphiphile is substantially higher (Delta T-m = 15-20 degrees C) than that of peptides without lipidation. The assembly process driven by the hydrophobic tail may provide a general method for creating well-defined protein molecular architecture using a minimalist peptide-based approach.