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Before May 2010, normal-orthometric heights were categorised using orders based on observation method and survey significance. This order framework was replaced by the Standard for the Geospatial Accuracy Framework (LINZS25005) and Standard for Tiers, Classes and Orders of LINZ Data (LINZS25006), and has been adopted for New Zealand Vertical Datum 2016. The old framework continues to be used for the existing local vertical datum.

The New Zealand Geodetic Datum 2000 (NZGD2000) deformation model is used to adjust coordinates for ongoing crustal deformation. It takes into account tectonic motion and some major earthquakes to ensure that coordinates of survey marks and other features track the movement of those marks over time.

An important feature of a geodetic datum is the reference surface. The reference surface approximates the shape of the Earth, so that geodetic coordinates can be located on a curved surface. The most common reference surface for geodetic datums is an ellipsoid.

The mathematical parameters and equations used to convert New Zealand Map Grid coordinates to other datums and projections.

Coordinates can be transformed between projections within the same datum, or between projections using different datums.

How to transform heights between vertical datums.

Coordinates can be transformed between geodetic datums by using either a transformation grid or a similarity transformation. This section includes examples of transforming to and from New Zealand Geodetic Datum 2000 (NZGD2000).

How to use the spatial map to search for property records and survey information such as marks and vectors.