The influence of two sources of individual differences in acquiring knowledge from maps was studied: abilities and learning procedures. Twenty-five undergraduate students provided verbal protocols while attempting to learn two maps, and six effective learning procedures were identified: partitioning, imagery, memory-directed sampling, pattern encoding, relation encoding, and evaluation. Visual spatial ability was highly correlated with recall of spatial attributes of the map and with overall learning performance, while associative memory ability was most correlated with verbal attribute recall. Subject-selected procedures for encoding spatial information and assessing learning progress also distinguished the behavior of successful and less successful learners. However, subjects of high and low ability differed little in the study procedures they chose. Although both ability differences and procedures were important contributors to performance, a direct comparison indicated that abilities are most predictive of map learning. It was concluded that the use of effective study procedures can influence map learning performance and that high-ability subjects benefit more from the use of these procedures than low-ability subjects. This report includes 27 references and an appendix detailing learning procedures observed in the protocols. (LMM)