Scientists say it's possible a tsunami on the scale of the one which hit Samoa in September could hit New Zealand.
A team from GNS Science and the National Institute of Water and Atmospheric Research (NIWA) has spent two weeks carrying out field work in Samoa and American Samoa.
The waves which hit Samoa were up to 14 metres above sea level.
A risk engineer from NIWA, Dr Stefan Reese, says some lives were saved in Samoa because people were educated about the risks, and chose to leave as soon as the earthquake happened.
He says if people feel a really strong earthquake they should move to safer ground, as there won't be a tsunami warning for a wave generated locally.