The party, led by Donald Tusk, had roots in the Solidarity movement. It advocated free market economy and individual liberty (however in Catholic understanding), rejected extremism and fanaticism and favoured European integration (in the form of European Union membership), rapid privatisation of the enterprises still owned by the Polish state and decentralisation of the government.
Until 1991, was a part of the Centre Agreement led by the Kaczyński brothers. In the 1991 general elections KLD got 7.5% of the votes and 37 seats in the Sejm (total 460 seats). In 1993 KLD got 4.0% of the votes and was left without seats.
It merged on March 20, 1994 with the Democratic Union (Unia Demokratyczna) into the Freedom Union (Unia Wolności, UW). In January 2001, some of the former KLD members decided to move to join the new Civic Platform. The KLD group within Civic Platform is now seen as moderate conservative. The liberal faction within Civic Platform is small and insignificant, represented by such politicians as Bartłomiej Sienkiewicz and Adam Szejnfeld.
