The independent reviewers examining New Zealand's intelligence and security legislation are asking the public to tell them what they think about the spy agencies.
One of the two reviewers, former deputy prime minister, Sir Michael Cullen, said public trust in the GCSB and the Security Intelligence Service (SIS) could be strengthened if they were more open.
He said some overseas agencies were becoming more open, and that helped the public understand what the agencies did and why.
Sir Michael said unnecessary secrecy created distrust.
He said people may make submissions on the adequacy of agencies' powers and protections for citizens.
Public consultation is open until 14 August.