Investigations into forced flow separations arose from the limitations of capillary controlled flow in planar chromatography[5,8,31]. Capillary flow systems can neither provide an optimum flow nor a stable flow during development. Compared with an optimum mobile phase velocity throughout the development, the results are lower performance, restricted migration distances, and a longer separation time. Three approaches have been proposed for forced flow separations based on rotational planar chromatography (centrifugal force), over pressured layer chromatography (pneumatic force) and pressurized planar electrochromatography (electroosmotic force). Each method requires dedicated instrumentation, currently of limited availability.