Background: Radiotherapy and surgery are routinely utilized to treat extremity soft tissue sarcoma. Multiple radiation modalities have been described, each with advantages and disadvantages, without one modality demonstrating clear superiority over the others. Questions/purposes: We determined the overall initial complication rate in patients receiving surgery and radiotherapy, which specific complications were found when comparing different modalities, and whether combination therapy increased the overall rate of complications compared with surgery and single-modality radiotherapy. Patients and Methods: We retrospectively reviewed the records of 190 patients who received external-beam radiotherapy (141 patients), high-dose-rate brachytherapy (37 patients), or both (12 patients). We evaluated 100 men and 90 women (mean age, 57 years; range, 18-94 years) for tumor size and subtype, comorbidities, stage, grade, margin of resection, type of adjuvant treatment, and complications. Minimum followup was 3 months (mean, 40 months; range, 3-155 months). Results: The most frequent early complications in the high-dose-rate brachytherapy cohort were infection, cellulitis, and seroma and/or hematoma. In the external-beam radiotherapy cohort, chronic edema, fibrosis, and chronic radiation dermatitis were more frequently encountered. The total number of early complications and overall incidence of major complications requiring further surgery were similar among the three cohorts, but a larger number of patients in the high-dose-rate brachytherapy group required subsequent surgery for infection compared with the external-beam radiotherapy group. Conclusions: High-dose-rate brachytherapy decreases radiation exposure and allows shorter duration of treatment compared with traditional external-beam radiotherapy but has a higher perioperative wound complication rate. Level of Evidence: Level III, therapeutic study. See the Guidelines for Authors for a complete description of levels of evidence.