Treatment for idiopathic adhesive capsulitis or frozen shoulder of the shoulder is controversial. The hypothesis of the study is that intra-articular cortico- steroid injection in the early stages of idiopathic adhesive capsulitis will lead to a rapid resolution of stiffness and symptoms. This is a retrospective cohort study of only patients with stage 1 or stage 2 adhesive capsulitis. The diagnosis was made by history and physical examination and only when other causes of pain and motion loss were eliminated. Stage 1 adhesive capsulitis was defined as significant improvement in pain and normalization of motion following intra- articular injection. Stage 2 included patients who had significant improvement in pain and partial improve- ment in motion following injection. Seven patients with stage 1 and 53 patients with stage 2 comprised the baseline cohort. The mean age was 52 years (range: 30 to 78); 46 patients were female and nine patients had diabetes mellitus. Patients completed a physical examination as well as a shoulder rating questionnaire for symptoms and disability. Criteria for resolution were defined as forward flexion and external rotation to within 15° of the contralateral side and internal rotation to within three spinal levels of the contralateral side. Forty-four of the patients out of 60 met the criteria for recovery at a mean of 6.7 months. The mode and median time to recovery was 3 months. The mean score at final follow-up for 41 patients using the shoulder-rating questionnaire of L_Insalata was 90 (range 52–100). The mean time to recovery for the stage 1 patients was 6 weeks (range: 2 weeks to 3 months), and it was 7 months for stage 2 patients (range: 2 weeks to 2 years). Glenohumeral corticosteroid injection for early adhesive capsulitis may have allowed patients to recover motion at a median time of 3 months. In many cases, the patients had improvement prior to the 3-month mark; however, that was the routine time for follow-up. Patients with stage 1 disease tended to resolve more rapidly than stage 2 patients. Prompt recognition of stage 1 and stage 2 idiopathic adhesive capsulitis and early injection of corticosteroid with local anesthesia may be both diagnostic and therapeutic.