It took time to develop the capital capacities required to sustain unprecedented prison expansionism in England and Wales. In this chapter I draw attention to six decisive moments in our recent penal history when the material, intellectual and ideological foundations were laid for the prison estate we encounter today. I review the early policy development that underpinned the Thatcher government’s PSA Building Programme, and I examine the prominent role of private sector investment in sustaining prison expansionism through a period of significant reductions in public expenditure. I explore the transformational impact of the mid-1990s Emergency Accommodation Programme, and I reflect upon the political fallout from Lord Carter’s 2007 review of the prison system and his controversial proposals for the construction of new generation of ‘Titan’ prisons. The chapter concludes with an overview of prison estate ‘modernisation’ following the Global Financial Crash and the 2019 General Election.