After the Korean War, development of the helicopter as a transportation and weapons system capability resulted in new doctrine and subsequent organization of the airmobile division. With this came a requirement for new fire support doctrine. Thus, the central research question was: What role did fire support provide in the execution of airmobile doctrine, along with the new weapons systems onto the battlefields of Vietnam? To understand how fire support doctrine evolved, this thesis addresses three subordinate questions. First, what was the current fire support doctrine prior to the Vietnam War? Second, how fire support doctrine evolved in supporting airmobile combat operations on the Vietnam battlefield? The final effort centered on determining how these changes in fire support doctrine influenced future fire support doctrine. Two realizations were noteworthy. First, fire support doctrine changed very little from the end of World War II to the end of the Korean conflict. Secondly, operational tempo and reach of airmobile operations, coupled with new weapons significantly influenced changes to fire support doctrine. This thesis demonstrates how fire support doctrine evolved to meet the new challenges of supporting combat operations on a nonlinear and noncontiguous battlefield.