Rules of Engagement (ROE) are rules or directives to military forces (including individuals) that define the circumstances, conditions, degree, and manner in which the use of force, or actions which might be construed as provocative, may be applied. They provide authorization for and/or limits on, among other things, the use of force and the employment of certain specific capabilities. In some nations, ROE have the status of guidance to military forces, while in other nations, ROE are lawful commands. Rules of Engagement do not normally dictate how a result is to be achieved but will indicate what measures may be unacceptable.

Rules of engagement are orders to military and security forces.