We often need to monitor and coordinate multiple deadlines. One way to handle these temporal demands might be to represent future deadlines as a pattern of spatial relations. More specifically, we tested the hypothesis that multitasking reflects selective effects of coordinate (i.e., metric) relational processing. Participants completed two multitasking sessions under concurrent processing demands of coordinate versus categorical spatial information. We expected and observed that multitasking impairs concurrent coordinate, rather than categorical, spatial processing. In Experiment 1, coordinate-task performance was selectively decreased, while multitasking performance was equal under both load conditions. When emphasizing equal (primary/secondary) task-importance in Experiment 2, it was only multitasking performance that was selectively reduced under the coordinate-load condition. Thus, effective multitasking may partly reflect coordinate-relational processing.