NCI's National Clinical Trials Network (NCTN) is a collection of organizations and clinicians that coordinates and supports cancer clinical trials at more than 2,200 sites across the United States, Canada, and internationally. NCTN provides the infrastructure for NCI-funded treatment and primary advanced imaging trials to improve the lives of people with cancer. NCTN clinical trials help to establish new standards of care, set the stage for approval of new therapies by the Food and Drug Administration, test new treatment approaches, and validate new biomarkers. The NCTN Navigator allows Investigators to query from available biospecimens, and to request biospecimens using the Letter of Intent (LOI) form. The request will go through a feasibility review process using one or more Feasibility Reports. After the Feasibility Report(s) are complete, the Investigator will be able to complete a Proposal form . After the Proposal form is submitted to the Front Door Service (FDS) Concierge for review, it will go through a scientific review process, which will include a Core Correlative Sciences Committee (CCSC) review decision.