This companion to Guides to the Evaluation of Permanent Impairment, Fifth Edition, provides instruction on a standardized method for measuring range of motion (ROM). The Guides Fifth assumes the user is experienced in measuring range of motion. This manual provides basic to proficient guidance that will enable physicians, physical therapists, and other evaluators to obtain accurate ROM measurements using standardized guidelines, reference tables, and reporting protocols. This consistent approach promises to produce greater intra- and interevaluator reliability. To increase accuracy, trained clinicians identify anatomic landmarks and properly position or stabilize the body to use a consistent technique to apply the measurement to the joint.