Abstract: A method for authorizing a user for a control access to at least one wind turbine or at least one wind farm is disclosed. In this method, a certification center first authenticates a user, and the certification center accepts a control-access type from the authenticated user. The certification center then generates an electronic certificate according to the accepted control-access type and/or according to stored access permissions of the authenticated user. Then the certificate is used for authentication with the wind turbine or with the wind farm for the purpose of performing a control access. A system for performing the method and also relates to a certification center and to an interface of a wind turbine or of a wind farm.