With consumer goods, as weil as consumer durables, the market is obscured because of product differentiation, in for example, the use, of trade marks, and the advertising and get-up of products, and this presents arealproblern in the protection of consumers. After a general demarcation of the forms, techniques and functions of product differentiation, an investigation is made into the correlation between the law and product differentiation; first, regarding pharmaceutical products and, then, though only by way of reconnaissance, for foodstuffs and cosmetics. Both in the general descriptive part and in the parts dealing with various sectors, attention is also paid to product differentiation as a source of the geographical division of markets. In a later chapter, certain general Observations on the law and socially undesirable product differentiation are developed. Here special attention is paid to trade mark law and regulations relating to misleading and dishonest advertising. The survey shows that, in the light of the existing economic model, improved consumer protection against the representation of product differ ences which hardly exist, can best be effected by means of regulations and other initiatives concerned with the supply of information, such as labelling requirements. September 1981 Dr. Jules Stuyck IX Table of Contents The first figure indicates the subsection number and the second figure the page number.