This collection of essays is concerned with three major and debated topics in international economics, namely interdependence between countries, real and financial integration, and the conflicting relations between industrialized (North) and developing countries (South). The first section deals with the international policy coordination problem and the economic growth of open economies. In the second section new foundations for commercial policy and the problems of economic integration, real and monetary, are discussed. The final section includes an analysis of North-South relations and of price instability of primary commodities.