This is an application for support for the core facilities of the Reproductive Endocrinology Center, University of California San Francisco. The Reproductive Endocrinology Center is an integrated, interdepartmental research and training Organized Research Unit of the University of California. Currently there are sixteen academic staff members of the Center, which has as its foci studies of the hypothalamic-pituitary-gonadal-target tissue axis and the endocrine physiology of the pregnancy. The core facilities include: 1) Radioimmunoassay Laboratory, 2) Hormone Binding Laboratory, 3) Morphology Facility, 4) Primate Facility, 5) Tissue Culture Laboratory, 6) Reproductive Clinical Research Unit, and 7) Administration. The existence of these core facilities will increase collaboration and interchange between the members of the Reproductive Endocrinology Center and avoid unnecessary duplication.