The purpose of this contract is to provide support for the clinical and basic research staff of the NICHD Intramural Program. The Contractor will perform assays of steroid and peptide hormones on samples of blood, urine, and saliva from NICHD patients and research animals. These assays may number as many as 100,000 per year. The Contractor will also work with NICHD staff members to provide tight quality control on all assays and will be available to discuss and effectuate alterations in procedure to meet the changing needs of the investigators. This service is essential for the functioning of the two clinical branches and two of the basic research laboratories of the NICHD. The needs of the NICHD for hormone assays simply outstrip the in-house capabilities of the Clinical Center Clinical Chemistry Section.