We examined the effect of background music on reading comprehension. Because the emotional consequences of music listening are affected by changes in tempo and intensity, we manipulated these variables to create four repeated-measures conditions: slow/low, slow/high, fast/low, fast/high. Tempo and intensity manipulations were selected to be psychologically equivalent in magnitude (pilot study 1). In each condition, 25 participants were given four minutes to read a passage, followed by three minutes to answer six multiple-choice questions. Baseline performance was established by having control participants complete the reading task in silence (pilot study 2). A significant tempo by intensity interaction was observed, with comprehension in the fast/high condition falling significantly below baseline. These findings reveal that listening to background instrumental music is most likely to disrupt reading comprehension when the music is fast and loud. (Contains 1 figure.)