The conflicting results observed in many lexical decision studies may have occurred because variables controlled in some studies were not controlled in others. In the present experiment, homophony, homography, word frequency, letter string length, part of speech, and concreteness were controlled in a lexical decision task. For word strings, reaction times were faster for high frequency nonhomographs than for low frequency nonhomographs but no differences were found between the reactions times for high frequency homographs and high frequency nonhomographs. No differences occurred between low frequency words and a variety of pseudowords. From these results, word frequency appears to be a relevant factor in word recognition. Since low frequency words and pseudowords have similar reaction times in a lexical decision task, it appears that pseudowords are processed in the same way as unfamiliar words, by their orthographic regularity.