This chapter reflects on the rivalry between Saudi Arabia and Iran's impact on Bahrain and Lebanon. Using concepts of capital, habitus and field found in the social theory of Pierre Bourdieu, it argues that the rivalry between Riyadh and Tehran plays out both within the 'transnational field' of regional politics but also in the 'domestic political fields' of Bahrain and Lebanon as Saudi Arabia and Iran seek to deploy capital in pursuit of power. The chapter suggests that the presence of regional powers in domestic politics reflects the importance of domestic political fields in shaping the transnational field, but also the reserves of capital - predominantly religious, economic, political and coercive - that Riyadh and Tehran are able to deploy across the region. The nature of domestic political fields conditions the ability of Riyadh and Tehran to exert influence, meaning that particular forms of capital resonate in some fields but not in others. As such, to better understand the rivalry between Saudi Arabia and Iran, we must look at the interplay between regional and domestic politics, and the ways in which such contestation and competition play out.