A synthetic approach to polyamides containing the tyrosine leucine linkage is presented. The diphenyl phosphoryl azide coupling technique was utilized to synthesize the monomer, tyrosylleucyliminohexamethyleneiminoleucyltyrosine. Solution polymerization of this monomer with adipoyl and sebacoyl chlorides resulted in polymers with intrinsic viscosities of 0.18 and 0.13 dl g-1, respectively, in 90% formic acid. Interfacial polymerization yielded a fibrous crosslinked material. The latter was found to be a poly(amide-ester) by i.r. spectroscopic analysis.