The important issue is that the person carrying out work is competent to do that work whether they are unlicensed or licensed staff. 145.A.30 (e) requires the MRO to establish and control the competence of persons involved in all aspects of maintenance. The AMC goes on to explain that the procedure should ensure the competence of all staff before they carry out unsupervised work, this includes certifying staff. A licence does not automatically equate to competence.