Operational Error Reporting and Central Monitoring Agency (CMA) Activities Background 5.10.1 In March 1980, the NAT SPG realised that after implementation of a 60 NM lateral separation minima, special importance would have to be placed on monitoring and assessment of navigation performance. It was therefore agreed that there was a need to collect, collate and circulate to States participating in the monitoring programme, data regarding navigation performance in the NAT Region To meet this requirement, the NAT CMA was established. 5.10.2 In the early s, as a consequence of the planned implementation of RVSM in NAT MNPS Airspace, the NAT CMA took on the responsibility for monitoring height-keeping performance. Initially, this was limited to collating data on operational errors but when the technical height-keeping programme came into being, the CMA became the data collection and collation centre. It has also become responsible for setting the target monitoring requirements for the RVSM approval process. Information about the CMA and current monitoring targets can be accessed through the Internet at http://www.nat-