The effects of intraserial repetition were tested using a probeless memory search task. Reaction time was facilitated in Experiments II and III only if the task involved alphabetical comparisons suggesting that repetition affects a comparison stage. The results of Experiment III revealed that the location of an item and its repeat in the set is an important variable since repetition effects were found only if the item and repeat were adjacent in the set. The results were supportive of an information reduction model in which stimulus sets containing repetition are reduced. Set reduction occurs more readily for the adjacent repetition condition due to the identical items being perceptually distinct. Support for a trace strength model prediction that only repeated target letters would facilitate RT was not found. / Master of Science