High resolution in gel permeation chromatography has been accomplished by use of long columns, since commercial rigid gels afford relatively fixed capacity ratios and since plate numbers of equivalent columns are additive. To overcome the high cost and high pressure requirement of long columns often required to resolve discrete species, high resolution gel permeation chromatography may be attained in commercial GPC equipment by recycle operation through the reciprocating pump, GPC column, and detector. However, peak width increases with the number of cycles (μ). Since the contained volume of the closed recycle system is constant, asvincreases the peak width (W) of the distribution will eventually exceed the volume of the system and peak overlap will occur. This presentation considers the increase inWand provides a method of “flush and draw off” to prevent sample overlap. Analytical and preparative scale separations were investigated, using both small and macromolecules. The effects of sample load and flow rate on-resolution with recycle operation were investigated.