TICAS (Taxonomic Intra Cellular Analytic System) for cell identification, developed by Wied et al, has for ultimate purpose computer discrimination among cells which by ordinary optical or cytochemical approaches cannot be differentiated from one another. The system is based essentially on pattern recognition methods with a series of complex analytical and statistical routines. The purpose of this project is to apply the principles of the TICAS system to the study of cells in the urinary sediment. The equipment consists of a Zeiss SMP scanning microscope with automatic stage on line with a PDP 12 computer (8K) using APAMOS (Automatic Photometric Analysis of Microscopic Objects by Scanning) program for collection of data. Cell scanning takes place at 0.5 micron interval automatically after visual identification. Cell images, collected as points of light transmission on LINC tape, are "cleaned" on the computer to eliminate any contamination of background, and stored on tape. Preliminary analysis of results performed on the PDP 10 computer at the University of Chicago disclosed that the computer classification of benign cells carried with it an error of 6%, whereas the identification of malignant cells carried with it an error of only 3%. The computer in Chicago successfully reproduced accurate cell images obtained in New York. The most important parameter utilized by the computer was the texture of nuclear chromatin, which reflects both granularity and staining density of the nucleus. Further work is in progress.