In the present study, we evaluated the failure and revisions rates after arthroscopic subacromial decompression (SAD). We examined 83 patients who were treated with arthroscopic subacromial decompression for primary shoulder impingement (stage II and stage III according to Neer) at an average follow-up time of 30 months. Hereby, special attention was paid to the revision operations resulting from our treatment. In patients with impingement stage II, the mean follow-up Constant-score was 84.7 (SD +/- 16.7) while in patients with impingement stage III it was 78.0 (SD +/- 21.8). In ten patients (12%) revision operation had to be performed, nine of them with initial stage II impingement and one with initial stage III impingement. Reasons for revisions were persisting or increasing pain as well as functional dissatisfaction. At the follow up examination, six of these revised patients (60%) were satisfied with the result. The mean follow up Constant-score in the revised patients was 77.3 (SD +/- 17.4). In 60% of the revised patients the necessity for the revision operation was directly related to the technical problems at the primary operation, in 40% we found reasons not related to the primary SAD. Technical falls are the most common cause for the need of revision operations after SAD. This demonstrates how demanding this kind of operation procedure is. In case of revision operations individual strategies should be developed in which the decision whether to perform arthroscopic or open revision procedures is of special importance.