Car workers’ union activism has long held a strong grip on popular memories of the post-war period. Working in the quintessential industry of modernity, their labour militancy has been linked to narratives of economic decline and of rising working-class living standards.Yet despite their centrality to understanding of this period, car workers’ capacity for collective action has often been taken for granted, with mobilisation attributed to uncomplicated economic motivations or the last gasps of a declining ‘traditional class consciousness’ and the effects of the post-war settlement.This book looks at the changing forms of agency and subjectivity expressed by labour militancy, considering workplace activism in the motor industry as a specific historical creation of post-war Britain rather than a reflection of ‘tradition’. It traces the origins of shop-floor organisations, which first emerged in the 1950s, studying the processes by which workers built their union cultures and exploring the capacity of car workers to generate new solidarities and collective values in this period.Focus then turns to the 1960s and 1970s and the social practices and cultural norms that resulted from this cultural assembling, looking to understand how worker activism shaped the agency of car workers in post-war Britain, influencing the forms that strike action took. Through a mixture of oral history interviews, letters, meeting minutes and periodicals, this book analyses the meanings workers attributed to industrial conflict, asking whether factory activism generated attitudes distinct from the dominant values of wider British society.