Rehabilitation programs are prescribed for many of those who incur the estimated 3 to 17 million sport- and recreation-related injuries sustained annually in the United States (Booth, 1987; Kraus & Conroy, 1984). Failing to adhere to sport injury rehabilitation programs can have an adverse impact on rehabilitation outcomes (Hawkins, 1989; Meani, Migliorini, & Tinti, 1986; Satterfield, Dowden, & Yasamura, 1990). Similarly, there is evidence that high levels of adherence to rehabilitation are associated with more favorable outcomes (Brewer et al., 1998; Derscheid & Feiring, 1987; Quinn, 1996; Tuffey, 1991). Consequently, researchers have attempted to identify predictors of adherence to sport injury rehabilitation. As noted in a recent review of the literature (Brewer, 1998), factors related to sport injury rehabilitation adherence include personal characteristics (e.g., personality), situational characteristics (e.g., social support for rehabilitation, perceived injury severity), cognitive responses (e.g., causal attributions), emotional responses (e.g., mood disturbance), and behavioral responses (e.g., instrumental coping). In one of the first empirical investigations of adherence to sport injury rehabilitation programs, Fisher, Domm, and Wuest (1988) administered the Rehabilitation Adherence Questionnaire (RAQ) to athletes who had completed injury rehabilitation. The RAQ is a self-report inventory with subscales designed to assess (a) perceived exertion, (b) pain tolerance, (c) self-motivation, (d) support from significant others, (e) scheduling, and (f) environmental conditions. Fisher et al. found that high scores on each of the subscales were associated with better adherence to clinic-based sport injury rehabilitation protocols. The RAQ has been used in two additional retrospective, clinic-based studies. Byerly, Worrell, Gahimer, and Domholdt (1994) found that higher scores on the subscales for pain tolerance and support from significant others were related to better rehabilitation adherence. Fields, Murphey, Horodyski, and Stopka (1995) obtained positive associations between rehabilitation adherence and scores on the subscales for pain tolerance, self-motivation, support from significant others, and scheduling. Despite some consistency in the findings of studies using the RAQ, particularly with respect to the subscales for pain tolerance and support from significant others, research with the RAQ is limited in two important ways. First, because of their retrospective designs, the studies could not establish a timeÐorder relationship (a prerequisite for inferring causality) between the psychological factors assessed by the RAQ and rehabilitation adherence. Second, because no reliability and validity data have been reported for the RAQ, it cannot be assumed that the RAQ subscales are stable or consistent measures or that they measure what they are intended to measure. Therefore, the purpose of this investigation was to examine the psychometric properties of the RAQ using a prospective research design.