The present invention relates to peptidomimetic ORL-1 receptor ligands containing certain conformationally constrained amino acids that favor alpha-helix or extended beta-strand conformations. Preferably, the ORL-1 receptor ligands of the present invention have one or more residues in an "address" segment to promote alphahelix formation. The ligands of the present invention include ORL-1 receptor agonists that may be used as analgesics to treat pain in a patient in need of such treatment, and also may be used to treat anxiety, addiction, withdrawal and drug tolerance, as well as to enhance memory and learning.
