During the next three years we plan to continue the development, refinement, and calibration of our analytical system. We now carry out routine chromatographic analysis of about 250 constituents of urine followed by computerized pattern recognition procedures. The number of substances that we measure will be increased and the effectiveness with which we extract useful clinical information from these measurements should improve. We have been applying this analytical system to a wide variety of health-related experiments. Experiments will emphasize mental and behaviorial abnormalities of children. We also have a continuing interest in the application of these techniques to adult mental illness, but we anticipate that sampling difficulties will limit this part of our research during the next three years.