In spontaneous speech, speakers sometimes replace a word they have just produced or started producing by another word. The present study reports that in these replacement repairs, low-frequency replaced words are more likely to be interrupted prior to completion than high-frequency words, providing support to the hypothesis that the production of high-frequency words is more automatic than the production of low-frequency words (Bybee, 2002; Logan, 1982). Frequency appears to have an effect on interruptibility even when word duration is statistically controlled. In addition, the frequency of the replaced word is positively correlated with the frequency of the word it is replaced by, supporting the hypothesis that high-frequency words are easier to access in production (Kittredge, Dell, Verkuilen, & Schwartz, 2008): the more frequent the target, the more frequent an inappropriate word needs to be to overcome the target and be uttered, only to be replaced. (Contains 1 table, 12 figures, and 14 footnotes.)