What is required for an implementation of IT Service Management to be successful?

A.
A top-down approach whereby the management of the organization strongly and visibly enforces the implementation

B.
Buy-in specifically from the levels in the organization which will be operationally involved in IT Service Management activities

C.
The appointment of a specialist department responsible for the development of the process structures

D.
The involvement and commitment of personnel at all levels in the organization from operational staff to top management