This text is devoted to the Political Parties Archive [Archiwum Partii Politycznych; http://archiwumpartiipolitycznych.pl] in the Institute of Political Studies of the Polish Academy of Sciences. The archive has been in operation since 1993 and is presently undergoing reorganization, which chiefly consists in digitalization. The author presents the idea behind the archive, its history, the classification of its resources, and above all, the information that can be found in it. The collected materials (printed, visual, online) provide information not only about the political parties currently operating in Poland (program documents, election campaigns, participation in social and political life) but also information on the period of systemic transformation and the formation of the democratic system from its beginnings, when opposition political circles in the Polish People’s Republic were working on plans for the future. The author emphasizes that the main characteristic of the archive is the activeness of its operators in obtaining materials (through queries to parties and state institutions, interviews with politicians, and monitoring election campaigns, including the archivization of audio-visual materials). The aim is to understand the mechanisms of political life. The Archive is supposed to have an educational function and by making its information accessible it should increase the transparency of political life.