A key part of the April 1998 Belfast Agreement addresses the vexed question of the disarmament (or decommissioning) of illegal sub-state paramilitary groups in Northern Ireland. In the current situation, the paramilitaries are unwilling to dispose of their considerable stocks of illegal weaponry, so the threat of renewed violence and its use as a bargaining card remain. The author examines the issue of decommissioning and the reason why it is a vital part of the peace agreement. He looks at the modalities and methods of decommissioning and the powers and role of the independent international commission which is supposed to oversee and verify the actual process of decommissioning. There is an analysis of the illegal weaponry held. In its various forms, decommissioning is vital for the building of communal confidence and the future stability of Northern Ireland.