Alternative civilian service, also called alternative services, civilian service, non-military service, and substitute service, is a form of national service performed in lieu of military conscription for various reasons, such as conscientious objection, inadequate health, or political reasons. Alternative service usually involves some kind of labor.
A conscientious objector is an "individual who has claimed the right to refuse to perform military service" on the grounds of freedom of conscience or religion. The term has also been extended to objecting to working for the military–industrial complex due to a crisis of conscience. In some countries, conscientious objectors are assigned to an alternative civilian service as a substitute for conscription or military service.
A number of organizations around the world celebrate the principle on May 15 as International Conscientious Objection Day.