We have developed a system for direct scanning gel chromatography which is under direct control of a SYM-1 microprocessor which is in turn under control of a PDP 1104. Each scan consisting of ∼200 data points of a 20-cm column may be obtained in as little as 3.5 s. Up to 100 scans may be obtained automatically without operator attention. A series of data manipulation programs have been written to allow determination of centroid migration rates, time difference chromatography calculations, etc. In conjunction with a mass transport simulation program it is possible to rapidly fit observed chromatography profiles. Use of the system to determine dispersion coefficients is described.