The Radiation Free Radical Research Core (RFRRC) facilitates Holden Comprehensive Cancer Center (HCCC) researcher investigations that require radiation services or quantitative methods for analyzing and manipulating redox status and redox based biological changes. It serves both HCCC members and cancer researchers at other institutions. The RFRRC has been in operation since 1947, and is directed by Douglas Spitz, PhD; Frederick Domann, Jr, PhD; Garry Buettner, PhD; and Prabhat Goswami, PhD all of whom have extensive experience and international reputations in free radical-focused cancer research. The RFRRC provides three basic services. Ionizing radiation services are supplemented by phosphorimaging and cell-cycle analytical tools critical to understanding basic cellular behavior and responses to radiation and chemotherapy. Electron paramagnetic resonance spectroscopy and other analytical chemistry detection methodologies are available for measuring free radicals, singlet oxygen, small molecule antioxidants, nitric oxide and the array of related oxidants and oxidative damage products. Antioxidant enzyme services provide easy access to technologies for modifying and measuring molecules responsible for pro-oxidant formation and oxidative damage. Major equipment available in the RFRRC includes several radiation sources, a Seahorse analyzer, various types of spectrophotometers, hypoxia chambers, and equipment for HPLC separation and analyte detection. The RFRRC provides HCCC members with easy access to specialized knowledge, reagents, equipment and resources in a highly collaborative and helpful environment.