The purpose of the Hormone/Metabolite Core Laboratory is to make available to DRC investigators a variety of analytical techniques that are of interest in the study of diabetes, atherosclerosis, obesity, insulin resistance and related problems. The services provided are best based in a Core Laboratory because they require special instrumentation and methodology which would be difficult or impractically expensive to establish in the laboratories of the individual investigators who are Users of the DRC. The Hormone/Metabolite Core Laboratory has been in operation since 1980 as part of the New York Obesity Research Center. We have now broadened the research base of this Core by making it available to the Columbia University DRC. In addition to being financially and technically expedient, the incorporation of the hormone/metabolite core in the DRC will facilitate scientific interactions between the diabetes research community in the Health Sciences campus and the New York Nutrition Obesity Research Center (NORC) at Columbia University. The closer association has been encouraged by the leadership of Columbia University as a way of coordinating scientific efforts, while maximizing utilization of existing resources and reducing the need for additional facilities, an expensive commodity in Manhattan.