Objective: To assess the clinical outcomes of types of exercise in the management of subacromial impingement syndrome. Design: Systematic review of randomized controlled trials. Methods: Studies were identified from databases searched to May 2009: MEDLINE, EMBASE, CINAHL, Sports Discus, PEDro, AMED, Cochrane Library, National Research Register, Index Chiropractic Literature. Two reviewers selected studies meeting inclusion criteria. The methodological quality of the included studies was independently assessed by two reviewers using the PEDro quality assessment tool. Results: Eight studies with sample sizes ranging from 14 to 125 were included in the systematic review and appraised for content. Four papers achieved a score of 6 or above indicating good quality, with the remaining four achieving 4 or lower, indicating poor quality. Synthesis showed only limited evidence to support the use of exercise in the treatment of subacromial impingement syndrome. Conclusion: There is a need for further well-defined clinical trials on specific exercise interventions for the treatment of shoulder dysfunction including subacromial impingement syndrome.