A novel series of melatonin receptor ligands, characterized by a N-(substituted-anilinoethyl)amido scaffold, along with preliminarystructure-activityrelationships (SARs), is presented. MT1 and MT2 receptor binding affinity and intrinsic activity have been modulated by the introduction of different substituents on the aniline nitrogen, on the benzene ring, and on the amide side chain. Modulation of