Brown (chemistry, University of Rhode Island) presents reviews of major developments in chromatography and the application of new analytical methodologies in separation science. Subjects include the prediction of retention and optimization in separation using gradient elution in liquid column chromatography, supercritical fluids for off- line sample preparation in food analysis prior to chromatography, solid-phase microextraction as a new tool in contemporary bioanalysis, polyelectrolytes as stationary phases in liquid chromatography, and a stochastic approach to the correspondence between chromatography, single-molecule dynamics, and equilibrium.