In most non-naval military services that are land-based (except the U.S. Army, where an executive officer is the second-in-command of certain units) or in joint military organizations, the executive officer is an administrative staff position versus a command position. XOs in these positions typically assist a commander or deputy commander (or in the case of joint staffs or joint commands, a director) by managing day-to-day activities such as management of the senior officer's schedule, screening of documents or other products, and oversight of the senior officer's administrative support staff.