This guide is intended to provide an introduction to the techniques and procedures used to evaluate and repair existing concrete structures post-tensioned with unbonded single-strand tendons. This guide demonstrates how the strength and serviceability of a structure that has experienced deterioration can be evaluated and restored to its original—or greater—strength and serviceability. Post-tensioning design, evaluation, and repair requires specialized knowledge. There is no substitute for experience and knowledge in working with post-tensioned structures. An experienced contractor and licensed design professional team is essential when working with post-tensioned structures. [Replaces 210.2–2002 (Evaluation) AND 320.4–2006 (Repair)]