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Abstract: L-Mandelic acid-1,2-O-(4-vinylphenyl)boronate (2) was copolymerized with divinylbenzene to yield a highly crosslinked macroporous polymer. 59% of incorporated L-mandelic acid (used as template) could be split-off on hydrolysis. The resulting polymer, with phenylboronic acid groups in the chiral cavities of type P1, was equilibrated in a batch process with D,L-mandelic acid in acetonitrile. The change of covering percentage, and that of the efficiency for racemic resolution, with time were followed by acidimetric titration and measurement of the optical rotation. A reasonable mechanism for the polymer-substrate interaction could de deduced. The selectivity terms for each of the forward and reverse reaction could be separately evaluated. Diffusional limitations significantly affect the observed efficiency of racemic resolution. Thermodynamically controlled separation, attainable by a suggested exchange reaction, required much more time than the considerably less effective kinetically controlled separation