János Kornai (til 1945 J. Kornhauser, born January 21, 1928), born in Budapest, Hungary, is an economist noted for his analysis and criticism of the command economies of Eastern European communist states.

Overcentralization in Economic Administration was the first book written by an East European and published in the West that openly criticized socialist central planning. Now reissued with a new preface, this book discusses issues that remain fundamental to any sound analysis of economic organization. Here Janos Kornai began a lifelong study of the economic organization of centrally planned economies. He identified several systemic failures of the centrally planned economy, and gave a prescient account of weak economic performance and eventual disintegration. Kornai's aim was to observe the reality of the working socialist system, and to draw conclusions that were not distorted by the laws of Marxist political economy. He provided a thorough positive analysis of conditions, along with normative recommendations which influenced the Hungarian reform process, culminating in the economic changes of 1968. Kornai's argument for radical rather than partial change makes this book timely and interesting reading for those involved in the economics of transition taking place in Eastern Europe today.