Book excerpt: The law on marketing and advertising has undergone profound changes based on the EU directives on unfair commercial practices and misleading and comparative advertising. The legislation partially requires full harmonisation and contains a comprehensive blacklist of prohibited practices. However, in other areas, only minimum harmonisation is required. A comprehensive case law from the CJEU has emerged, but still many issues remain open, unclear and debated. The EU Commission has an active interest in the field and has published numerous reports on the question. In addition it has developed revised, comprehensive guidelines on marketing business to consumer (B2C), which are fully discussed here. Further Commission initiatives in the area on business to business (B2B) marketing are also in the making, underlining the importance of this new collection.