Background and Purpose. Purtilo, Guccione, and others have noted that increased clinical autonomy for physical therapists presents more complex ethical dilemmas. The body of literature examining physical therapy ethics, however, is relatively small and has not been analyzed. The primary purposes of this research were: (1) to use multiple perspectives to describe and analyze literature examining ethics in physical therapy from 1970 to 2000, (2) to develop a model to describe the evolution of knowledge of ethics in physical therapy during this period, and (3) to compare the proposed model with the evolutionary models proposed by Purtilo in physical therapy and by Pellegrino in bioethics. Sample. The sample consisted of peer-reviewed journal articles cited in the MEDLINE or Cumulative Index to Nursing and Allied Health Literature (CINAHL) databases between 1970 and 2000 or referenced in Ethics in Physical Therapy. Methods. A two-phase mixed quantitative and qualitative method was used to analyze publications. In the quantitative phase, the author sorted publications into a priori categories, including approach to ethics, author, decade, country of publication, role of the physical therapist, and component of morality. During the qualitative phase of the research, the author analyzed and sorted the publications to identify common themes, patterns, similarities, and evolutionary trends. These findings were compared with the evolutionary models of Pellegrino and Purtilo. Results. The 90 publications meeting inclusion criteria were predominantly philosophical, using the “principles” perspective; focused on the patient/client management role of the physical therapist; and addressed the moral judgment component of moral behavior. As predicted by Purtilo's model, the focus of identity evolved from self-identity to patient-focused identity, with increasing representation of societal identity. Recurrent themes included the need to further identify and clarify physical therapists' ethical dilemmas, the interrelationship between clinical and ethical decision making, and the changing relationship with patients. Discussion and Conclusion. Although knowledge of ethics grew steadily between 1970 and 2000, this retrospective analysis identified gaps in our current knowledge. Further research is needed to address the unique ethical problems commonly encountered in all 5 roles of the physical therapist; patient perspectives on ethical issues in physical therapy; variety in ethical approaches; factors affecting moral judgment, sensitivity, motivation, and courage; and cultural dimensions of ethical practice in physical therapy.