In the fall of 1989, after years of political and economic crises, communist regimes in Czechoslovakia, Hungary, and Poland collapsed. Due to their common historical development, particularly during the Austrian Empire era, they are often treated as a specific region inside the Soviet bloc. After the regime change, in 1991, the countries confirmed their close ties formally by setting up the Visegrad Group and followed a common path that led them to accession to the European Union in 2004. The similar political development after 1989 has also been reflected in the area of political financing. Two factors, one internal and one external, significantly contributed to this similarity: first, as in all post-communist countries, political parties were being created from the top down and needed money for their activities and campaigning. With no ties to the civil society and virtually no membership, only small sums were collected from membership fees and private donations and parties had to turn to the state for financial support. Public funding schemes therefore became a hallmark of post-communist party systems, including the party systems of Czechoslovakia (since 1993, the Czech Republic and Slovakia), Hungary, and Poland. Second, the countries of the post-communist East Central Europe became members of the same international organizations, including the European Union and the Council of Europe. These supra-national bodies put considerable pressure on their post-communist member states to tackle corruption in their political systems. In 1999, Hungary, Poland, and Slovakia were among the first members of the Group of States against Corruption (GRECO), the Council of Europe’s anti-corruption monitoring body. The Czech Republic joined in 2002. Since then, the four countries, together with the remaining 45 GRECO members, have shared many anti-corruption standards, including standards on the transparency of political financing. This chapter presents the development of political finance and campaign funding regulations in the four individual countries in greater detail. While the history of the respective national party systems is briefly touched upon, the focus lies on the most recent developments and the current state of party funding regulation and practice in these countries. *This research was supported by the Czech Science Foundation, project No. 16-25570S “Political Financing in Central Europe on the National and the Sub-National Level”.