Method for authorizing users for control accesses to at least one wind turbine or at least one wind farm, comprising the steps: - a certification centre authenticating and authentifying a user, - the certification centre accepting at least one control-access type from the authenticated user, - the certification centre generating an electronic certificate containing the control-access type according to the accepted control-access type and/or according to stored access permissions of the authenticated user for authentification of control access containing the control-access type at the wind turbine or the wind farm, and - using the certificate for authentication with the at least one wind turbine or with the at least one wind farm for the purpose of performing control accesses having the control-access type wherein a) the certificate containing a validity period is generated and the control system is used to store for each control-access type a maximum total number and certificates are generated for a control-access type only if the number of the certificates that have already been awarded and are currently valid on the basis of their validity period lies below the maximum total number, or b) the certificate containing a validity period is generated and the control system is used to store for each control-access type a maximum number per predefined region, and certificates are generated for a control-access type only if the number of the certificates that have already been awarded for the region and are currently valid on the basis of their validity period lies below the maximum number per predefined region. - a certification centre authenticating and authentifying a user, - the certification centre accepting at least one control-access type from the authenticated user, - the certification centre generating an electronic certificate containing the control-access type according to the accepted control-access type and/or according to stored access permissions of the authenticated user for authentification of control access containing the control-access type at the wind turbine or the wind farm, and - using the certificate for authentication with the at least one wind turbine or with the at least one wind farm for the purpose of performing control accesses having the control-access type wherein a) the certificate containing a validity period is generated and the control system is used to store for each control-access type a maximum total number and certificates are generated for a control-access type only if the number of the certificates that have already been awarded and are currently valid on the basis of their validity period lies below the maximum total number, or b) the certificate containing a validity period is generated and the control system is used to store for each control-access type a maximum number per predefined region, and certificates are generated for a control-access type only if the number of the certificates that have already been awarded for the region and are currently valid on the basis of their validity period lies below the maximum number per predefined region. a) the certificate containing a validity period is generated and the control system is used to store for each control-access type a maximum total number and certificates are generated for a control-access type only if the number of the certificates that have already been awarded and are currently valid on the basis of their validity period lies below the maximum total number, or b) the certificate containing a validity period is generated and the control system is used to store for each control-access type a maximum number per predefined region, and certificates are generated for a control-access type only if the number of the certificates that have already been awarded for the region and are currently valid on the basis of their validity period lies below the maximum number per predefined region.