The Autonomous Region in Muslim Mindanao (ARMM) is an autonomous region of the Philippines, located in the Mindanao island group , that consists of five predominantly Muslim provinces. It is the only region in the Philippines that has its own government.
Link to the official ARMM website.
ARMM has a Regional Governor, Executive departments, and its own unicameral legislature, the Regional Legislative Assembly. It has no judiciary or separate court system - the Philippines court system applies to the region. It does not enter into foreign relations, and has no military. Philippines laws also apply to the region, as well as the ARMM's own laws.
The Constituent Act of the ARMM is the ARMM Organic Act (Republic Act No. 6734)
Up to date Executive, Administrative and Memorandum Orders are also available in English from the ARMM website in the Issuances menu.