NRG Oncology is a newly constituted NCI National Clinical Trials Network (NCTN) network group created through the coordinated efforts of the National Surgical Adjuvant Breast and Bowel Project (NSABP), the Radiation Therapy Oncology Group (RTOG), and the Gynecologic Oncology Group (GOG) with a primary vision of improving the lives of adult patients with localized or locally advanced malignancies through the conduct of high quality NCI-supported multi-institutional clinical trials. NRG Oncology (or NRG) has leveraged the tremendous resources, leadership, membership, and history of practice-defining research of the three legacy groups to create a modern clinical and translational research organization with the capability to execute clinical and translational research trials for adult patients with common and rare malignancies in the following disease sites: Gynecologic Cancer (including Ovarian, Cervix and Endometrial Cancer); Brain Tumors (Primary and Secondary); Breast Cancer; Gastrointestinal Cancers (Colorectal and Non-Colorectal Cancers); Genitourinary Cancer; Head and Neck Cancer; and Lung Cancer. NRG will be the leading network group defining new standards of care and scientific paradigms for several of these disease sites. For these seven cancer disease sites, NRG will primarily conduct trials for patients with early or intermediate stage cancers testing innovative diagnostic and therapeutic approaches, including novel imaging, radiation oncology, and surgical approaches; the integration of novel systemic agents or classes of systemic agents with optimized loco-regional therapies and existing systemic therapies, and the use of biomarker- and biologic pathway-defined approaches to risk stratification, investigational therapy assignment, and clinical trial decision-making. The group has seven scientific core committees and four integrated committees which provide both scientific support and generate protocols: Developmental Therapeutics (DT), Translational Science, Patient-Centered Outcomes Research, and Cancer Prevention and Control Committees. NRG's DT Committee builds on the GOG DT Committee's success in enrolling over 500 patients/year on early phase trials leading to phase III trials. The NRG Operations Center is fully aligned with NRG Oncology Statistical and Data Management Center (SDMC) and the NRG Biorepositories and will be fully compliant with all NCI regulations and proactive in improving the efficiency and quality of its research. The group will serve as a scientific resource for other NCTN network groups for radiation oncology innovation through its Center for Innovative Radiation Oncology (CIRO).