This study is an examination of the Vietnam War dissent offered by Republican Senator George Aiken of Vermont during the years of the Lyndon Johnson Presidency. Emphasis is placed on analyzing the level of influence Aiken's criticisms had on American policy in Vietnam. Aiken's influence on his fellow Senators, particularly his Republican colleagues, is examined, as is the question of whether Aiken's dissent played a role in reducing the intensity of the conflict. The study explores in detail the individual years from 1964 to 1968, the particular debates concerning the war raised among Senators in each of these years and the role that Aiken played in these debates. The study also examines the nature of Aiken's dissent and its relation to that offered by other Senators both Republican and Democrat. Aiken's position as a Republican is shown to have given a bipartisan character to anti-war dissent in the Senate; this was vital in providing such dissent with an added level of legitimacy.