The monograph, for the first time in Russian historiography, based on extensive factual material and available publications, comprehensively and systematically studies the activities of state security agencies in organizing and developing the partisan movement in the occupied territory of Belarus in 1941–1944. Previously unpublished archival documents were introduced into scientific circulation, which made it possible to reveal various areas of activity of employees of state security agencies and their role in transforming the partisan movement into a serious force, which became one of the factors of victory in the Great Patriotic War. This publication examines the contribution of state security agencies to increasing the combat effectiveness of partisan formations, measures to expand the scale of the partisan movement and increase its effectiveness, the main areas of activity of the special services behind enemy lines, forms and methods of work, features of reconnaissance, counterintelligence, sabotage and other operations. The book may be useful to specialists in the history of the Great Patriotic War , as well as everyone who is interested in military history. The publishing layout of the book is saved in PDF A4 format.