This paper investigates how people acquire knowledge from maps. Emphasis is placed on heuristics--defined as the procedures that people use to select, combine, and encode map information in memory. The objective is to develop a theory of expertise in map learning by analyzing differences between fast and slow learners in terms of differences in their learning heuristics. The document is presented in five sections. Section I introduces the scope of the research study. Section II explains the knowledge acquisition process. Section III analyzes four types of learning processes involved in map learning--attention, encoding, evaluation, and control. Specific skills discussed include systematic sampling, counting, memory-directed sampling, association, evaluation, and pattern encoding. Section IV analyzes differences in learning styles among eight individuals during a map drawing exercise. Findings indicated that subjects who stressed certain heuristics (including imagery, pattern encoding, and memory directed sampling) were able to reproduce maps from memory more correctly than subjects who stressed other heuristics (including evaluating material already learned and random sampling). The final section offers conclusions including that good learners differ from poor learners in their ability to encode spatial information, evaluate learning progress, and focus attention in accordance with a learning plan. Additional research is suggested on training people to use successful heuristics. (Author/DB)