Background and Purpose. This study investigated physical therapist assistants' (PTAs) perceptions of the documented roles of PT As and compared those perceptions with those of physical therapists from a previous study. Subjects and Methods. A questionnaire that described 79 physical therapy activities was distributed to a sample (n=400) of PTAs derived from the American Physical Therapy Association membership. The response rate was 56% (n=225). Respondents indicated whether each activity was included in the documentation describing PTA roles. Discriminant analyses were used to determine whether demographic factors predicted the pattern of responses. In addition, meta-analytic techniques were used to determine whether PTA responses were different from those of physical therapists gathered previously. Results. The greatest agreement of PTA opinions with published guidelines occurred for treatment implementation activities, and the lowest level of agreement occurred for items designated as administrative activities. Responses of PTAs were different from those of physical therapists on 21 of the 79 activities. The greatest number of these differences occurred for evaluative functions (n=9). Physical therapist assistants’ perceptions of documented PTA roles were generally less consistent with published guidelines than were those of physical therapists. Conclusion and Discussion. Physical therapist assistants' perceptions of the roles of the PTA were, for some activities, not consistent with written guidelines. Using the data provided in this study, discussions to revise the documentation of the scope of PTA practice may focus on those activities for which disagreement between PTAs and physical therapists exists and for which opinions differ markedly from published guidelines.