The Spaso technique consists of forward flexion, external rotation, and gentle traction for the reduction of anterior shoulder dislocations with the patient in the supine position. The aim of this prospective study was to assess clinical efficacy of the Spaso technique and to evaluate its complications. We prospectively evaluated 52 shoulder dislocations using the Spaso technique. All reductions were performed by residents in training. Rescue methods if initial reduction was unsuccessful were at the discretion of the treating physician. Fifty-two patients were enrolled and 39 (75%) dislocations were successfully reduced without anesthesia or assistance. The mean reduction time was 3.2 min, and 87% of successful reductions occurred in less than 5 min. If we exclude the first 20 cases as a learning period, the success rate increases up to 87.5%. There were no complications associated with using the Spaso technique in this series. Patients with concomitant greater tuberosity fractures and late presentation had a lower success rate, although this was not statistically significant. The Spaso method is effective in reducing anterior shoulder dislocations without anesthesia or assistance and may decrease reduction time and length of stay in the Emergency Department.