The Alliance for Clinical Trials in Oncology (Alliance), one of five National Clinical Trials Network groups, serves as the parent organization for the Alliance NCI Community Oncology Research Program (NCORP) Research Base (Alliance NCORP). The Alliance NCORP conducts interventional and observational clinical and translational research as well as database studies – all of which address important questions relevant to cancer prevention, symptom control, and cancer care delivery. In addition, the Alliance NCORP conducts clinically important quality of life studies that are embedded within cancer treatment trials. It places special emphasis on minority, underserved and older patients at risk for or diagnosed with cancer, and on building strong collegial relationships with NCORP Community sites and Minority/Underserved Community sites. The Alliance NCORP committee membership includes rich representation from both community-based and academic medical centers, as well as patient advocates, thus generating research results relevant to cancer patients across the United States. The Alliance NCORP also emphasizes mentorship and training of junior investigators. Over this past grant cycle, i.e., since August 2014, the Alliance NCORP has published 148 manuscripts and abstracts. This work has included practice-changing research in such areas as the prevention of chemotherapy-induced nausea and vomiting, the prevention of skeletal-related events from osseous metastases, the management of brain metastases, and the integration of patient-reported outcomes into cancer clinical trials. The Alliance NCORP conducts translational research that requires the collection of tumor tissue, premalignant tissue samples, blood, and other human biospecimens; and shares data and biospecimens for pooled analyses and other scientific collaborations. These biospecimens create an invaluable repository for understanding clinical observations from a mechanistic standpoint. The Alliance NCORP also collaborates broadly with other NCI-funded investigators and consortia, as well as with investigators supported through non-NCI sources. This practice-changing research and the scientific questions answered by the Alliance NCORP provide meaningful and innovative contributions to clinical and translational oncology, which can be conducted only within a publicly-funded research network.