Purpose: The purpose of this study was to determine if either open or closed kinetic chain exercises were clearly superior in terms of decreasing pain or disability related to shoulder impingement. Hypothesis: There will be no significant difference in outcomes as measured by pain and disability caused by shoulder impingement between subjects who participate in either an open kinetic chain (OKC) or a primarily closed kinetic chain (CKC) exercise program to improve rotator cuff and scapular strength and endurance (Null Hypothesis). Subjects: Participants were drawn from a convenience sample of patients who presented to physical therapy for treatment of pain and/or decreased shoulder function at one (1) of five (5) physical therapy clinics in the state of Washington. Methods: After potential subjects were identified and met all inclusion criteria, informed consent was obtained and subjects were randomly assigned to one of two exercise groups. One group performed exclusively open kinetic chain exercises for rotator cuff and scapular strengthening and endurance. The second group performed primarily closed kinetic chain exercises targeting the same muscle groups. Exercise frequency was established at four (4) sessions per week for six (6) weeks. To ensure exercises were performed and progressed correctly, all subjects were scheduled for two (2) sessions per week for three (3) weeks then once weekly for two (2) weeks with a therapist who was trained in the exercise programs and progression. Home exercise flow sheets were used to track at home exercise compliance for the remained of the sessions. Data was collected regarding the changes in activities of daily living, pain levels via the Shoulder Performance and Disability Index (SPADI) and a medication usage form before a subject’s first exercise session and again at the completion of all scheduled exercise sessions. Results: A total of forty-five (45) subjects completed all exercise sessions. There were six (6) subjects who dropped out. Twenty-two (22) completed the OKC exercise protocol and twenty-three (n=23) the primarily CKC program. The two (2) groups were compared regarding age, gender, baseline pain and baseline function sub scales of the SPADI and acuity (duration of symptoms). There were no significant differences (p=0.05) between the groups prior to beginning the exercise protocols. After completion of all exercise sessions, both groups showed a significant (p=0.05) decrease in disability and pain subscale scores. The differences were, however, not significant from each other. (Accept the Null Hypothesis). Between-group comparisons were made using Wilcoxon rank sum tests and confirmed using two sample t-tests. Conclusion: There were no significant differences between the two (2) exercise groups related to decreased disability or pain as measured by the SPADI. There was, however, a significant improvement noted in both groups from pre to post exercise scores. Due to the small sample size there might be minor differences between the groups post exercise scores that were not identified by this study.