A sidebar titled “Rating Impairment for [complex regional pain syndrome] CRPS Type 1” in the March/April issue of The Guides Newsletter states: “Do NOT use the pain chapter to rate CRPS” because there is no well-defined pathophysiologic basis. That conclusion is contradicted by the pain chapter, which lists CRPS among conditions considered ratable, but accompanying text provides no explanation how this determination was made. This article attempts to resolve the conflict between the sidebar in The Guides Newsletter and the pain chapter. The lack of a well-defined pathophysiologic basis for CRPS is the reason for the position stated in the sidebar, and a review of the relevant professional literature confirms this reasoning. Further, the concept of CRPS itself is ambiguous and was intentionally designed to be “general” and “descriptive” and historically has been diagnosed using nonstandardized, idiosyncratic, or incompatible diagnostic systems. The AMA Guides to the Evaluation of Permanent Impairment is self-contradictory regarding diagnostic criteria and terminology (eg, is CRPS-1 synonymous with RSD, causalgia, or neither?). CRPS lacks any well-defined pathophysiology, is highly ambiguous and controversial, involves characteristics that compromise the credibility of any examinee making such a presentation, and is a good example of a condition that should be evaluated using the mental and behavioral disorders chapter.