Polish semi-presidentialism evolved from a pacted transition between the leadership of the communist regime and the Solidarity opposition movement. The mechanics of semi-presidentialism, as well as its effect on democratisation, depend upon the constitution, the party system and the personality of the president. Poland has had three semi-presidential constitutions, a variety of relationships between president and government as well as government and parliament, and two very different presidents. In the early years, the absence of the conditions for stable semi-presidentialism had a negative effect on democratisation. Later on, conditions were more supportive, and semi-presidentialism began to play a more positive role. Before the introduction of semi-presidentialism in November 1990, Polish elites had already established a firm consensus on democracy, which was buttressed by consensus on the economic system and international relations. Therefore, the conflicting legitimacies generated by semi-presidentialism delayed but did not prevent, or seriously threaten, democratic consolidation in Poland.