The main objective of this paper was to determine the reasons for adopting a strategy of
collaboration in the executive arena by one of the mainstream right parties in Poland in 2006.
To demonstrate the potential motivations for cooperation with the extreme right, coalition
formation theories – office, policy and vote - have been applied. Conclusions drawn from the results of application of formal coalition theories (based on quantitative studies) have been verified in an in-depth case study and then compared with results from similar research in Western Europe. Another aim of this paper was to determine the conditions and mechanisms underlying the formation of a coalition with an extreme right party, which theories are not equipped to expose. Particular attention was paid to factors resulting from the party system, the specificities of political parties, the participation of other actors external to the political scene, and behavioral matters. The research has shown that the inclusion of the radical right in government coalitions was motivated primarily by the prime minister party's desire to realize office and policy-related objectives. At the same time the party was forced to compromise on vote-related goals. These conclusions confirmed the predictive capabilities of formal coalition formation theories, and the validity of the suggestions resulting from them concerning the motives for forming the coalition. The case study also revealed the functioning in Poland of more general truths identified in Western Europe, such as the electoral shift to the right of the mainstream right party and the tendency to a softening of the extreme right when it is engaged in cooperation. It has also demonstrated the divisions typical of post-communist states which affect patterns of political rivalry and cooperation, and finally government formation patterns. The study also showed indirect factors specific to Poland that facilitated the formation of a coalition with the extreme right.
