Surgery is generally considered as the only curative therapy for pancreatic cancer; however, even with optimal surgery, long-term cure is achieved in very few patients, thus highlighting the need for adjuvant therapies. Radiation therapy, usually in combination with chemotherapy, plays a role in the setting of unresectable, nonmetastatic pancreatic cancer. Its role in the adjuvant setting remains controversial and as yet undefined. This article reviews the role of radiation therapy in the adjuvant and definitive settings, and describes recent improvements in the delivery of radiotherapy that allow for improved dose delivery with decreased toxicity.