OBJECTIVE: To search the English-language literature for original research addressing the effect of cryotherapy on return to participation after injury. DATA SOURCES: We searched MEDLINE, the Physiotherapy Evidence Database, SPORT Discus, the Cochrane Reviews database, and CINAHL from 1976 to 2003 to identify randomized clinical trials of cryotherapy. Key words used were cryotherapy, return to participation, cold treatment, ice, injury, sport, edema, and pain. DATA SYNTHESIS: Original research, including outcomes-assessment measures of return to participation of injured subjects, was reviewed using the Physiotherapy Evidence Database (PEDro) Scale. Four studies were identified and reviewed by a panel of certified athletic trainers. The 4 articles' scores ranged from 2 to 4 on the PEDro scale, which has a maximum of 10 points. Two of the articles suggested that cryotherapy speeds return to participation after ankle sprains. However, these authors failed to provide in-depth statistical analysis of their results. A confounding factor of compression as part of the treatment prevented interpretation of the effects of cryotherapy in 1 article. CONCLUSIONS: After critically reviewing the literature for the effect of cryotherapy on return-to-participation measures, we conclude that cryotherapy may have a positive effect. Despite the extensive use of cryotherapy in the management of acute injury, few authors have actually examined the effect of cryotherapy alone on return-to-participation measures. The relatively poor quality of the studies reviewed is of concern. Randomized, controlled clinical studies of the effect of cryotherapy on acute injury and return to participation are needed to better elucidate the treatment responses.