[3][4] The NAB is responsible for collecting and analysing information on external matters which may affect New Zealand, including foreign states, individuals, and events.
It draws its information from a range of public and confidential sources including the Security Intelligence Service (NZSIS), Government Communications Security Bureau (GCSB), New Zealand diplomatic posts, academic discourse, the media, and other publicly available sources.
Its role is to interpret and process information from other sources, producing reports which may be used as a basis for decision-making in other branches of government.
[2] The National Assessments Bureau's origins can be traced back to the Joint Intelligence Office (JIO), which was established in 1949.
In March 2010 the EAB was renamed the National Assessments Bureau (NAB) and given a domestic security focus as well.