This article offers some theoretical reflections on how to categorize or type 1960s radicalism - termed as the 'Movement' here - in the USA and Britain. Particular reference is made to the work of Karl Mannheim, notably to his use of the concepts of 'generation' and 'utopia' and related terms. The article concludes that the radical 'generational unit' or student movement of the 1960s, despite weaknesses, was in certain respects 'societally' or 'realistically utopian' rather than manifestly 'unrealistic' as some critics have argued. References supportive of the main argument are made to Mills and Marcuse’s understanding of 1960s radicalism and to data based on interviews with a number of British and American activists. It is argued that the strong cultural theme of 1960s radicalism is highly characteristic of its realistically transcendent utopian character.