Inhaltsangabe:Abstract: The Awkward Partner (AP) Thesis is a widespread theoretical framework which explains why Britain has been called a semi-detached member of the European Union. This paper aims to take on the AP thesis by calling into question its basic tenets. To do this, the thesis? claims and initially detectable flaws have to be set out explicitly. But the main challenge shall be launched by examining the Single European Act (SEA) in detail. Resulting contradictions and the implications of the findings require further answers: Should the AP thesis be abandoned? If not, how can it be revised? The argument advanced here is that the AP thesis presupposes a negative behaviour by UK governments vis-?-vis their European counterparts. This is explained by endogenous constraints that are imposed upon the core executive. These constraints are mainly caused by the divergence of domestic political forces. Slow and different rates of adaptation to the EU decision-making level are to be emphasised. While central government has already adjusted to the EU level, it attempts to retain its ?gatekeeper? role between domestic and European political spheres. In contrast to the AP thesis, this paper shall show that in the run-up to the SEA Britain was not more negative than other member states. The UK representatives made proposals and concessions, as did everyone else. Despite the contradiction between theory and empirical study, it shall here not be concluded to abolish the AP thesis, ...