“Sandwich” adjuvant therapy (radiation therapy sandwiched between six total cycles of chemotherapy) for Stage IIIC endometrial cancer evolved as a solution to reduce distant recurrence and minimize locoregional recurrence while limiting toxicity in order to achieve optimal therapeutic dosing of both radiation and chemotherapy. Multiple retrospective and prospective analyses show superior survival outcomes and acceptable tolerability with “sandwiching” radiation between chemotherapy. A prospective randomized trial including a treatment arm in which chemotherapy is given before radiation or sequenced in a “sandwich” fashion to maximize local and systemic control is necessary to determine the optimal adjuvant therapy for Stage IIIC endometrial cancer.