This chapter considers the breakdown of Labourism in relation to six interwoven themes: the crisis of socialist ideology; structural change in post-war society; electoral vulnerability; organisational atrophy and fragmentation; the demise of social democratic institutions; and Labour’s historical failings as an effective governing party. The crisis of Labourism encouraged intellectuals to consider the impact of the ‘New Times’ on the shape of Left politics. Labourism remained an elusive identity primarily relating to the ethos and culture of the British Labour movement, its attributes of loyalty and defensiveness focused since the nineteenth century on safeguarding the material interests of the working class. The New Labour project was a comprehensive response to the long-term collapse of Labourism in British politics. The debate about the crisis of Labourism fashioned New Labour’s agenda for national reform and modernisation, and was animated by overarching themes that are elaborated further below. An additional facet of the crisis of Labourism related to the party’s electoral viability.