In late November 2007, Commissioner Kroes announced the adoption of Guidelines for the assessment under the EU Merger Regulation of companies in a vertical or conglomerate relationship. Vertical mergers are those between companies with activities at different levels of the supply chain in the same market whereas conglomerate mergers involve companies in neighbouring or related markets. The Guidelines explain the circumstances where such mergers may limit effective competition, and provide examples based on economic principles. The new Guidelines are intended to complement those adopted earlier concerning horizontal mergers (i.e. between companies competing in the same product and geographic market).