The development of the Diagnostic Criteria for Temporomandibular Disorders (DC/TMD) (1) involved expanding the taxonomy for all TMDs (2) in order to propose for future validation DC for empirically supported TMDs that were not part of the DC/ TMD structure. This expanded taxonomy offers an integrated approach to clinical diagnosis and provides a framework for operationalising and testing the proposed taxonomy and diagnostic criteria in future research. During expansion of the taxonomy, researchers identified several challenges in the diagnosis of some disorders, so the International RDC/TMD Consortium Network planned a workshop to discuss criterion improvements for five of the disorders and the biobehavioural domain.