The Deputy Chief of Naval Operations (VCNO) is the second highest-ranking commissioned officer of the United States Navy in the Department of the Navy and functions as the principal deputy to the chief of naval operations. By law, the VCNO is named a four-star admiral and is appointed by the President of the United States, requiring confirmation by a majority vote in the Senate. The VCNO is responsible for assuming the functions and responsibilities of the Chief of Naval Operations (CNO) in their absence or inability to perform their duties. The CNO is also assisted by other high-ranking officers, such as Deputy Chiefs of Naval Operations (DCNO), Deputy Chiefs of Naval Operations (ACNO), and other staff members collectively referred to as the Office of the Chief of Naval Operations (OPNAV).
The CNO is a four-star admiral and senior military officer in the Department of the Navy, appointed by the President with advice and consent from the Senate for a term of four years. This position was initially named Operations Assistant in 1915 and Deputy Chief of Naval Operations in 1922.The CNO is responsible for commanding, using resources, and ensuring operational efficiency for naval operating forces and Navy shore activities assigned by the Secretary of the Navy.