This chapter examines the political economy of British theatre – that is, how the state governs and manages the economics of theatre – and British theatre’s often fraught relationship to these arrangements. It considers the place where state funding of theatre has been most necessary but most reluctant: theatre buildings. The chapter first traces the history of capital investment in British theatre since 1945. It shows how the state has taken up its fiscal responsibilities to finance theatre building fitfully, and sometimes inequitably. Against this historical backdrop, the chapter then examines the reconstructed Battersea Arts Centre in south London, which fully re-opened in 2018 after a serious fire. The refurbished BAC, the chapter argues, makes a distinctive and persuasive case for public investment in theatre. Economically, it realises a Keynesian aim articulated at the foundation of the theatrical mixed economy after World War Two: for public investment to increase theatre’s productive capacity. It also puts the value of that investment on show, suggesting an alternative case for public funding, one in which theatre is not simply a ‘good cause’ but a highly credible investment, economically and aesthetically.