Egypt is a geographically large, populous and internationally-recognised state with an organised bureaucracy and armed forces. In contrast, Hamas is an armed social movement, which, after its electoral victory in January 2006 and, more importantly, after acquiring full control over the Gaza Strip in June 2007, emerged as a quasi-state with internal sovereignty. Egypt enjoys a peace treaty with Israel and a strategic alliance with the US, whereas Hamas is in conflict with Israel, and is designated by the US as a terrorist group. This thesis traces the interactions between Hamas and Egypt during the 2006-2014 period, with a focus on the Mubarak era. The dissertation’s main aim is not only to present how and when asymmetry and strategic differences between Hamas and Egypt were reflected in their relations, but also to explain why and how on certain occasions their interactions took on the form of tactical cooperation. Hence, I show that small or quasi-states in the contemporary Middle East are in position to extract political gains from larger neighbouring state actors even in the presence of strategic differences. This thesis contextualises the situations it discusses through Omni Balancing Theory (OBT), which understands an actor’s foreign policy as the outcome of the efforts of its leader to survive politically by balancing between external and internal threats. In this regard, Egypt’s approach towards Hamas and vice versa at a given time is seen as the result of a cost-benefit calculation that has assessed the value of simultaneous foreign and domestic threats. Accordingly, the dissertation looks at Hamas-Egypt relations through three lenses: firstly, through the impact of international and regional pressures; secondly, through cross-border interactions; and thirdly, through the effect of domestic pressures. Finally, the thesis separately discusses the course of Hamas-Egypt relations between February 2011 and August 2014. This is due to the density of the political developments during this period. To be precise, the three weak post-Mubarak Egyptian governments faced quite diverse threats the dealing of which generated considerable fluctuations in Cairo’s approach towards Hamas.