NACMA was the NATO ACCS Management Agency. It was responsible for the management of the NATO Air Command and Control System (ACCS) programme, which is a $500M project to provide the NATO commands with a new air command and control system from 2009 onwards.
On 1 July 2012 all staff and functions were merged into a new NATO Agency, the NATO Communications and Information Agency (NCIA), where the ACCS project is now managed by the NCIA AirC2 element..
References
NACMA Wikipedia(Text) CC BY-SA