(79)Insurance and reinsurance groups are free to decide on the specific internal arrangements, distribution of tasks and organisational structure within the group as they see fit to ensure compliance with Directive 2009/138/EC. However, in a few cases, such arrangements and organisational structures can jeopardise effective group supervision. Therefore, group supervisors should have the power - in exceptional circumstances and after consulting EIOPA and the other supervisory authorities concerned - to require changes to those arrangements or organisational structures. Group supervisors should duly justify their decisions and explain why the existing arrangements or structures obstruct and jeopardise effective group supervision.