Preoperative exercise/rehabilitation is currently being considered to improve outcomes for orthopaedic surgery. This article presents an evidence-based practice review of the current research literature from 1998 to 2008 to determine whether preoperative exercise alone will be beneficial to patients preparing for total knee or hip arthroplasty. Only 3 studies met the inclusion criteria of preoperative exercise as the sole intervention. Each of these studies indicated that preoperative exercise had some postoperative benefit to total knee or hip arthroplasty patients. In general, the results are inconclusive due to the lack of strong research evidence, and only a pragmatic recommendation for preoperative exercise prior to total hip or knee arthroplasty is supported. More research is needed in the area of preoperative exercise for persons preparing for total hip or knee arthroplasty.