The editor and associate editor of The Guides Newsletter respond to and comment on a letter by Knobler and Mandel and the response by Ensalada in this issue. Knobler and Mandel raise interesting issues, including the importance of a thorough medical evaluation and analysis in which the physician must differentiate, on the one hand, symptoms associated with a physical disease process and, on the other hand, illness behavior (symptom magnification) and somatization. Probable relationships must be differentiated from those that are only possible. For example Knobler and Mandel note that RSD can change, but permanent impairment is rated as the individual is, not as he or she will be in the future. The AMA Guides to the Evaluation of Permanent Impairment (AMA Guides) states that the degree of disability in the social and vocational contexts is not necessarily the same as the degree of impairment, and loss of function may be greater or less than the impairment might imply. Further, many factors can confound the relationships between impairment and disability, including motivation and illness behavior. The AMA Guides also states that the complexities of secondary gain and motivation complicate the assessment process. Finally, the AMA Guides is used to assess impairment; it was not designed to define disability.