**RG** A group of companies is a collection of companies with separate legal personalities, but maintaining direct and indirect links mainly financial (equity or control). And also frequently organizational (management), economic strategies or commercial (sales and purchases of goods or services). Such existence though with separate legal personalities, characterizes the notion of group. A business group is 'capped' by a company called a 'group header' not directly or indirectly controlled by another company and thus having at least one subsidiary. Property mode Such a group may be: * Public - owned by a state (or another public authority) under the supervision of a department. * Or cooperative - a company whose capital is held by cooperatives. * Or capitalist - (eg Mittal-Arcelor). In this case, the lead firm is usually a corporation acting as a financial holding company * Finally, there are mixed groups in which capital is distributed among private shareholders and the public (eg Volkswagen), or between private shareholders and regional cooperatives (eg credit or agricultural cooperative). The organization is usually in the form of corporate group. The group legally consists of a parent company known as a holding company (its subsidiaries). The types of organizations differ from one group to another, as well as corporate cultures, which can lead to inconsistencies in the short and long term reorganizations, mergers, acquisitions ... From a functional standpoint, the groups generally originate from a specific country and then spread. When they reach full stature Internationally (multinational), they adopt a functional country, regions, industries, etc. The groups listed on a stock market, usually at their parent companies are legally obliged to publish consolidated accounts.