This chapter discusses the United Kingdom’s participation in and response to the Base Erosion and Profit Shifting project. It starts with a short introduction on the UK’s economy, and its political and tax system (section 17.1). Second, this report provides an overview of the UK’s proactive and leading role in the OECD/G20 project (section 17.2). Third, it analyses the UK’s response to the BEPS project, including measures implementing BEPS minimum standards (section 17.3), measures in response to other BEPS actions (section 17.4) and some of the UK’s unilateral “BEPS” measures (section 17.5). Generally, the UK has been an enthusiastic and early adopter of BEPS proposals. Fourth, this chapter discusses the role of the UK tax administration in international tax reform (section 17.6). Finally, this chapter sheds light on the opportunities and challenges that characterise the UK’s international tax agenda (section 17.7).