In this work, we use question answering as a general framework for studying how eye movements in reading reflect the reader’s goals, how they are pursued, and the extent to which they are achieved. We leverage fine-grained annotations of task-critical textual information to perform a detailed comparison of eye movements in information-seeking and ordinary reading regimes. We further examine how eye movements during information seeking relate to question answering behavior. We find that reading times, saccade patterns and sensitivity to the linguistic properties of the text are all strongly and systematically conditioned on the reading task, and further interact with question answering behavior. The observed reading patterns are consistent with a rational account of cognitive resource allocation during task-based reading.