Thymomas are the most frequently encountered tumors of the mediastinum and often present with either localized or locally advanced disease. The prognosis in thymoma has been consistently shown to correspond to the invasiveness of the tumor (as represented by the Masaoka stage of the tumor) and the completeness of surgical resection. Because treatment with a variety of different chemotherapy regimens has demonstrated radiographic response rates greater than 50% in patients with advanced thymoma, a number of investigators have explored the use of preoperative (induction, neoadjuvant) therapy for patients with locally advanced thymoma. In this review, we summarize the published experience with preoperative therapy for thymoma and discuss ongoing clinical trials exploring multimodality therapy for treatment of locally advanced thymoma.