This chapter examines current conceptual and empirical thinking about economic regionalization within the global economy, particularly in light of debates about the potential retreat of economic globalization in the second decade of the twenty-first century. It provides an overview of theories of economic regionalization as well as how this concept relates to wider debates about globalization. In doing so, it argues that while there is both a deepening of economic regionalization in some parts of the global economy - and a new geography to this process - it does not represent an overall reversal of wider trends toward greater global economic integration. The chapter illustrates this argument through considering a number of examples at firm, industry and regional level.