A classroom teacher modified the behavior of a 10‐yr‐old student who had a high rate of obscene vocalizations accompanied by facial twitches. In the first phase, the subject was instructed to repeat rapidly the most frequent obscene word in four daily 15‐min sessions. This procedure reduced the frequency of obscene vocalizations, but not to an acceptable level. Subsequently, the teacher was able effectively to control the target behavior using a timeout proc