This article examines how semantic memory processes influence the items that are considered by decision makers in memory-based preferential choice. Experiments 1A through 1C ask participants to list the choice items that come to their minds while deliberating in a variety of everyday choice settings. These experiments use semantic space models to quantify the semantic relatedness between pairs of retrieved items and find that choice item retrieval displays robust semantic clustering effects, with retrieved items increasing the retrieval probabilities of related items. Semantic clustering can be disassociated from the effect of item desirability and can lead to inefficiencies such as the consideration and evaluation of undesirable items early on in the decision. Experiments 2A through 2C use a similar approach to study the effects of contextual cues on item retrieval and find that decision makers are biased toward retrieving choice items that are semantically related to the choice context. This effect is usually strongest early on in deliberation and weakens as additional items are retrieved. Overall, the results highlight the role of semantic memory processes in guiding the generation of memory-based choice sets, and illustrate the value of semantic space models for studying preferential decision making.