The purpose of this thesis is to evaluate the use and testing of the motorcycle by the US Army from April 1917 to February 1977. Procurement of the early military motorcycle for tactical operations ceased in 1939 because it could not operate off the road and was mechanically unreliable. In early 1972 the Modern Army Selected System, Test Evaluation and Review (MASSTER) began testing the modern motorcycle. It found that the problems experienced with the early motorcycle had been eliminated and that the modern motorcycle had considerable military potential. As a result of this testing, MASSTER recommended that the motorcycle be returned to the Army inventory as a scout and traffic control vehicle. Department of the Army believed the test was inconclusive and disapproved the recommendation. Testing of the motorcycle has continued since 1972 and has included tests by tactical units and the Armor School. The results of this testing and a survey of foreign armies indicate the motorcycle is suited for use as a messenger vehicle, traffic control vehicle, and scout transporter. However, only the use of the motorcycle as a scout transporter has made any progress along the acquisition cycle. The Infantry School has scheduled the testing of a scout motorcycle in June 1977. This test and other testing have overlooked the obvious potential and capability of the motorcycle as a messenger and traffic control vehicle. Thus the military value of the modern motorcycle has been recognized, but the US Army has failed to address the issue of total user requirements.