The gradual economic integration of Western Europe is bringing about far reaching changes in the countries taking part in the venture. One of the features of this process - and a prominent feature - is making itself felt in the field of industrial organization through a profound change in the structure of a large number of markets. In taking advantage of the larger market created by the elimination of national frontiers as barriers to trade, large firms playa leading role - firms from within the European Community and from outside. The merger device has been a major vehicle of expansion, and in several sectors of manufacturing industry this has already led to an in crease in the relative importance of a few firms. Over the years, public opinion has become increasingly aware of the con centration of industrial power and of itG attendant problems. Merger law and control of the operations of la:;e corporations are current topics of discussion. More especially, merger statutes have recently been enacted in Britain and Germany, and the matter is coming to be one of the chief pre occupations of the European Commission.