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.