Between 2000 and 2010, new institutional arrangements were created for UK broadcasting regulation, built upon a radical rethinking of communications policy. This article examines key changes arising from Labour's media policy, the Communications Act 2003 and the work of Ofcom. It argues that changes within broadcasting were less radical than the accompanying rhetoric, and that contradictory tendencies set limits to dominant trends of marketisation and liberalisation. The article explores these tendencies by reviewing the key broadcasting policy issues of the decade including policies on the BBC, commercial public service and commercial broadcasting, spectrum and digital switchover, and new digital services. It assesses changes in the structural regulation of media ownership, the shift towards behavioural competition regulation, and the regulation of media content and commercial communications. In doing so, it explores policy rationales and arguments, and examines tensions and contradictions in the promotion of marketisation, the discourses of market failure, political interventions, and the professionalisation of policy-making.