International human resource management (HRM) concerns the people management policies and practices of organisations that operate across international boundaries. A key component of IHRM is the management of expatriates (Dowling, 1999) but, as this book illustrates, the subject goes much wider (Brewster et al., 2005; Brewster et al., 2011). This has been contrasted with comparative studies of HRM (Boxall, 1995), the study of the way that HRM is thought about, works and the effects that various practices have in various settings (Brewster and Mayrhofer, 2012). It further concerns the relative impact of specific societal features on the practice of HRM, and how these vary between contexts (cf. Goergen et al., 2009a; 2009b). As these various fields have developed there have been increasing numbers of explorations of the way that these topics overlap (Brewster, 2012; Brewster and Mayrhofer, 2011). At the same time, the classic globalisation/ differentiation debate (mainly) within multinational corporations (MNCs) (Bartlett and Ghoshal, 1998) has been echoed in HRM as elsewhere (Bae et al., 1998; Brewster et al., 2008; Farndale et al., 2008; Festing et al., 2007); in other words, to what extent do MNCs serve as agents of homogenising global process. However, as the classic HRM literature alerts us, HRM is the issue on which local influences have most impact on MNCs (Rosenzweig and Nohria, 1994).