Communication and consequently advancement of knowledge in understanding and treatment of chronic pain has been hindered by the absence of a taxonomy of chronic pain syndromes. Recently the IASP Subcommittee on Taxonomy proposed a classification method based on a multiaxial system. In the present study the interjudge reliability of 2 of the 5 axes, body location and presumed etiology are evaluated. Overall, axis I demonstrated good reliability, however, the reliability of several categories contained within this axis were low enough to suggest minor changes to this axis may increase its clinical utility. Axis V was found to have only fair reliability and many of the categories comprising this axis were demonstrated to have reliabilities that are not clinically acceptable. The implications of these results for future development and refinement of the IASP taxonomy are discussed.