Staff colleges train military officers in the administrative, staff and policy aspects of their profession. It is usual for such training to occur at several levels in a career. For example, an officer may be sent to various staff courses: as a captain

Captain (OF-2)

The army rank of captain is a commissioned officer rank historically corresponding to command of a company of soldiers. The rank is also used by some air forces and marine forces. Today a captain is typically either the commander or second-in-command of a company or artillery battery...

 they may be sent to a single service command and staff school to prepare for company command and equivalent staff posts; as a major to a single or joint service college to prepare for battalion command and equivalent staff posts; and as a colonel or brigadier to a higher staff college to prepare for brigade and division command and equivalent postings.

The success of Staff Colleges spawned, in the mid-twentieth century, a civilian imitation in what are called administrative staff colleges.