This study focuses on the local (county) archival sources of the cooperative farms of Hajdú-Bihar county, and examines the possibilities of how to use them, besides some basic questions of the socialist era’s public- and social history. Within this, the thesis intends to enumerate the essential sources for the collective farms- and post-World War II agriculture research by highlighting the importance and utilization practice of the archival writings and collections (data warehouse, archival reference library, and oral history resources).