The importance of the control concept in companies’ restructuring operations may be analyzed from different perspectives: several interpretations arise in accounting, especially regarding group accounting, but given the evolution of IAS/IFRS some evolutions are expected. In many countries, the accounting treatments for mergers were not very restrictive and different solutions were applicable. But the convergence between company accounts and consolidated accounts draws attention on the issue of control. In order to analyze the implications of the concept of control, two cases are distinguished: the operations between entities under common control and the operations between previously independent entities. In the first case, the entities are already controlled and the operation is not an acquisition because the control is only reinforced or maintained.