Part 1 Synthesis and Characterization: F. Haviv and T.D. Fitzpatrick, Synthetic Approaches to Incorporation of Using Genadotropin-Releasing Hormone Animo Acids into Peptides. A.F. Spatola, Synthesis of Pseudopepfides. M. Chorev and M.P. Caulfield, Synthesis and Synthetic Manipulations of Peptides Derived from Parathoid Hormone and Parathoid Hormone-Related Protein. P.A. Anton, .F Shanaha, and J.P. Reeve Jr, Biotinylated Neuropeptide Analoges: Design and Use as Probes for Target Cells in Heterogeneous Populations. A.L. Smith, Using High-Performance Liquid Chromatography in Peptide Characterization and Purification. Part 2 Development and Use of Receptor Ligands: T. Inagami and Y. Kambayashi, Atrial Natriuritic Factors and Fragments. G.J. Trachte and B.J. Elmquist, Atrial Natriuritic Factors Binding to Clearance Receptors in Isolated Neuronal Membranes. E. Hazum and I. Schvartz, Biotinylated Endothelin Analogs as Probes for Endothelin Receptor. R. Miller, J.T. Pelton and C.R. Hiley, Analogs of Endothelin, C.W. Lin, T.A. Miller, B.B. Bianchi, and D.G. Witte, Selective Cholecystokinin A and Cholecystokinin-B/Gastrin Receptor Agonists. C.A. Maggi, Tachykinin Receptor Antagonists. K. Raynor and T. Reisine, Somatostatin Receptor Subtypes in Rat Brain Revealed by Somatostatin Analogs. N.A. Sharif, Thyrotropin-Releasing Hormone Analogs and Receptors. H. Shapiro, E. Wada, R. Jensen, and J. Battey, Distinguishing Bombesin Receptor Subtypes. J.P. Gies, A. Pifilieff, E.B. Haddad, and E. Lach, (Characterization Solubilization) Bombesin Receptor Subtypes. R.D. Smith, J.V. Duncia, P.J Lee, D.D. Christ, A.T. Chiu, D.J. Carini, W.F. Herblin, and P.B.M.W.M. Timmermans, R.R. Wexler, and P.C. Wong, Nonpeptide Angiotensin II Receptor Antagonist: Losartan. J. Howl and M. Wheatley, (Selective Biotinylated Probes) V1a Vasopressin Receptors: C. Barberis, T. Durroux, S. Audigier, M-N. Balestre, S. Jard, M. Manning, and W.H. Sawyer, V1a Vasopressin Receptors: Studies with a Radioiodinated Ligand. D. Butlen and A. Ammar, Pharmacological Identification of Vasopressin Receptors in Isolated Renal Tubule. Part 3 Development and Use of Antisera: R.W. Veh, H-W. Habbes, I.M. Grumbach, H.T. Pham, K-H. Meyer and J. Czekalla, Neuropeptide Conjugation to Carrier Proteins. M. Mori, T. Satoh, and M. Yamada, Anti-Idiotypic Thyrotropin-Releasing Hormone (TRH) Antibody. K. Rissler, H. Cramer, and G. Friedrich, (Influence of Oxidation State) 125I-Labelled Substance P on Sensitivity of Radioimmunoassay.