Background: Only a few studies have provided homogeneous analysis of open revision surgery after a failed arthroscopic Bankart procedure. Hypothesis: Open Bankart revision surgery will be effective in a failed arthroscopic anterior stabilization but inevitably results in a loss of range of motion, especially external rotation. Study Design: Case series; Level of evidence, 4. Methods: Twenty-six shoulders that went through traditional open Bankart repair as revision surgery after a failed arthroscopic Bankart procedure for traumatic anterior shoulder instability were enrolled for this study. The mean patient age at the time of revision surgery was 24 years ( range, 16-38 years), and the mean duration of follow-up was 42 months ( range, 25-97 months). Results: The preoperative mean range of motion was 173 in forward flexion and 65 in external rotation at the side. After revision surgery, the ranges measured 164 and 55, respectively (P = .024 and .012, respectively). At the last follow-up, the mean Rowe score was 81 points, with 88.5% of the patients reporting good or excellent results. After revision surgery, redislocation developed in 3 shoulders (11.5%), all of which had an engaging Hill-Sachs lesion and associated hyperlaxity (2+ or greater laxity on the sulcus sign). Conclusion: Open revision Bankart surgery for a failed arthroscopic Bankart repair can provide a satisfactory outcome, including a low recurrence rate and reliable functional return. In open revision Bankart surgery after failed stabilization for traumatic anterior shoulder instability, the surgeon should keep in mind the possibility of a postoperative loss of range of motion and a thorough examination for not only a Bankart lesion but also other associated lesions, including a bone defect or hyperlaxity, to lower the risk of redislocation.