The participant in this study was a boy with a long history of self-injurious face slapping. Following a functional analysis indicating that face slapping was maintained by sensory consequences, the participant was given soft wrist weights to wear for progressively longer periods. Data on the frequency of face slapping were collected 5 min before the weights were put on, while the weights were on, and 5 min after the weights were removed. At all other times a protective helmet was placed on the participant's head for 30 min contingent on face slaps. When weights were worn for 30 min each day, face slapping decreased during 5-min observation periods before and after wearing the weights. The use of protective headgear was eliminated by the end of the study. Face slapping did not occur during a follow-up check conducted 5 months after completion of the study.