Objective: The aim of this study was to determine how strongly the performance of navigation tasks is affected by changing electronic map interfaces and by individual differences in spatial ability. Background: Electronic map interfaces have two common configurations, north up and track up. Research suggests that north-up maps benefit some navigational tasks and track-up maps benefit others. However, little research has investigated how map configuration affects the important navigation task of judging cardinal direction or how individual differences in spatial ability interact with map configuration in affecting navigation performance. Method: In an aerial reconnaissance task, 16 participants completed route-following, cardinal direction, and map reconstruction tasks. Participants also completed three spatial ability tests. Results: The track-up map led to better performance on the cardinal direction and route-following tasks. The north-up map led to better performance on the map reconstruction task. Effects of map configuration showed small to medium effect sizes. Spatial ability correlated positively with performance of each navigation task, showing medium to large effect sizes. For some tasks, a helpful map interface compensated for low ability. For other tasks, ability facilitated the performance of the helpful interface; optimal performance required a helpful interface and high ability. Conclusion: Achieving high performance at particular navigation subtasks requires two things: using the map configuration that optimizes subtask performance and having high spatial ability. Application: Some aspects of navigation performance can be improved primarily by using the optimal map configuration; other aspects require using the optimal configuration and having better spatial ability.