The American Academy of Orthopaedic Surgeons has developed an Appropriate Use Criteria (AUC) on the Non-Arthroplasty Treatment of Osteoarthritis of the Knee (OAK). Evidence-based information, in conjunction with clinical expertise of physicians, was used to develop the criteria to improve patient care and obtain best outcomes while considering the subtleties and distinctions necessary in making clinical decisions. The OAK AUC clinical scenarios were derived from patient indications that generally accompany OAK as well as from the current evidence-based clinical practice guidelines and its supporting literature. The 576 patient scenarios and 10 treatments were developed by the Writing Panel, a group of clinicians who are specialists in this AUC topic. Next, the Review Panel, a separate group of volunteer physicians, independently reviewed these materials to ensure that they were representative of patient scenarios clinicians are likely to encounter in daily practice. Finally, the multidisciplinary Voting Panel (made up of specialists and nonspecialists) rated the appropriateness of treatment of each patient scenario using a 9-point scale to designate a treatment as Appropriate (median rating, 7 to 9), May Be Appropriate (median rating, 4 to 6), or Rarely Appropriate (median rating, 1 to 3). The final appropriateness ratings assigned by the voting panel can be accessed online via the AAOS OAK AUC web-based mobile application at: www.aaos.org/aucapp.