This article examines global social policy formation in the area of skilled migration, with a focus on the Gulf Arab region. Across the globe, migration governance presents challenges to multiple levels of authority; its complexity crosses many scales and involves a multitude of actors with diverse interests. Despite this jurisdictional complexity, migration remains one of the most staunchly defended realms of sovereign policy control. Building on global social policy literature, this article examines how 'domestic' labour migration policies reflect the entanglement of multiple states' and agencies' interests. Such entanglements result in what we characterize as a 'multiplex system', where skilled-migration policies are formed within, and shaped by, globalized policy spaces. To illustrate, we examine policies that shape the nursing labour market in Oman during a period when the state aims to transition from dependence on an expatriate to an increasingly nationalized labour force. Engaging a case-study methodology including a survey of migrant healthcare workers, semi-structured interviews and data analysis, we find that nursing labour markets in Oman represent an example of global policy formation due to the interaction of domestic and expatriate labour policies and provisioning systems. The transnational structuring of policy making that emerges reflects a contingent process marked by conflicting outcomes. We contend that Oman's nursing labour market is an example of new spaces where global social policies emerge from the tension of competing national state and market interests.