Part 6 of the Nigeria Civil Aviation Regulations provides regulations for the registration and monitoring of Approved Maintenance Organizations (AMO) by the Authority of Nigeria (NCAA). The proper maintenance of aircraft is fundamental to aviation safety, and requires meticulous record keeping. ICAO Annex 6 allows maintenance of aircraft under both an AMO that is approved by the State of registry or another Contracting State and is accepted by the State of Registry. It also allows for the maintenance of aircraft by a person or organization in accordance with procedures that are authorized by the State of Registry. This means that the AOC holder can either have its aircraft maintained in accordance with the maintenance program of the AOC holder approved by the Authority of Nigeria, if the AOC holder is also certificated as an AMO or by another AMO.