Two experiments examined the relationship between individual differences in phonological memory (PM) and the ability to learn determiner–noun agreement rules in semiartificial microlanguages. Participants were tested on their ability to induce the grammatical gender of nouns from the distribution of the determiners that accompanied them. Three measures of PM were found to be related to rule learning as assessed by a generalization test: phonological short–term memory, vocabulary learning, and memory for determiner–noun combinations early in the experiment. There were also statistically independent effects of knowledge of other gender languages, suggesting that both memory and nonmemory factors were related to learning outcomes.