The “imageability effect”-highly imageable words are easier to read than abstract words-has been found in cases of acquired dyslexia, developmental dyslexia, and even normal readers. The hypothesis that the imageability effect is a function of the differing ages at which imageable and abstract words are acquired was examined in the present experiment. Specifically, it was hypothesized that if the imageability effect is actually mediated by age of acquisition, then equating high- and low-imagery words for age of acquisition should eliminate the effect. Good and poor readers were required to indicate whether high- and low-imagery words (equated for age of acquisition) were identical to previously presented words and to indicate their confidence in their judgment. Good and poor readers did not differ in their ability to recognize formerly presented high- or low-imagery words. Subjects were also asked to read the words aloud. Reading latency was unaffected by word imagery for either reading group. It was concluded that the imageability effect is mediated by age of acquisition and that controlling this factor eliminates the effect.