Lesch–Nyhan disease (LND) is a rare X-linked recessive genetic disorder associated with cognitive impairment, choreoathetosis, hyperuricemia, and the hallmark symptom of severe and involuntary self-mutilation. This study examines data gathered from a survey of 64 families in the USA and abroad regarding the self-injury of their family members who have LND. The individuals with LND ranged in age from 1 to 40 years (mean 16 years 7 months, SD 11 years 2 months) and, with the exception of one, were males. The most common initial mode of self-mutilation, and the most frequently cited past or current behavior, was biting of lips and/or fingers. Other behaviors, in order of frequency, included head banging, extension of arms when being wheeled through doorways, tipping of wheelchairs, eye-poking, fingers in wheelchair spokes, and rubbing behaviors. Hierarchical cluster analysis identified patterns of association among the types of self-mutilation. Modes of self-mutilation in which external surfaces (such as a wheelchair component) served as instruments of self-injury tended to co-occur, as did biting of lips and fingers.