The Observer Group (precursor to Marine Corps Amphibious Reconnaissance Company and the Navy Scouts and Raiders) was a joint-United States Army/Marine Corps unit that was the first in the United States and Fleet Marine Force to be organized and trained specifically for amphibious reconnaissance. The Observer Group experimented in the methodology and equipment for projecting reconnaissance from the sea before the establishment of the OSS Maritime Unit, the Underwater Demolition Teams, and before the Army Special Forces and Air Commandos. It was also the birth of naval amphibious intelligence.