Cognitive mapping involves the description of the way individuals store and process geographic information. Typically, cognitivie mapping data are derived from individual responses and then analyzed in one of three ways: (1) the individual data sets are analyzed separately and only pooled for comparison (disaggregation); (2) the individual data sets are averaged and then analyzed (collective aggregation); or (3) the individual data sets are analyzed and the results averaged (individual aggregation). This paper compares the latter two aggregation strategies for analyzing cognitive mapping data using data collected in a large-scale study of students' configurational knowledge of the city of Swansea in the United Kingdom. It is contended that the aggregation strategy adopted will have a fundamental effect upon the conclusions drawn from a study.