This volume has been composed to commemorate the day, 25 years ago, that Dr. P. J. Verdoorn delivered his inaugural lecture after his appointment as professor of economics at the Netherlands School of Economics at Rotterdam. The prompt and enthusiastic reactions by several members of the profession on our request for a contribution illustrates the fact that Verdoorn is held in high esteem by those who worked with him and those who are acquainted with his work. We thank all the contributors for having helped us to realize our plan to honour Verdoorn with the publication of this 'liber...

Most re cent contributions to disequilibrium theory have a high level of abstraction. Empirical studies explicitly based on disequilibrium are still relatively scarce. However, empirical macro economics anticipated the theoretical development, and amalgamated classical and Keynesian elements often without a clear-cut formal base. Now a theoretical integration of neo-classical and neo-Keynesian economics seems under way. There is a renewed interest in the micro-economic foundations of macroeconomics with a special focus on the behaviour of economic agents operating in non-clearing markets. In...