The purpose of this guideline is to provide a coherent and practical guide to the application of the Joint Australian/New Zealand Technical Report, TR IEC 61000.3.6:2012, for limiting harmonic voltages in medium voltage (MV) and high voltage (HV) distribution networks, and to present a simplified approach that a particular DNSP may elect to adopt under certain circumstances. It should be understood that this guideline is not binding and the DNSP’s own harmonic management policies shall prevail. The Joint Australian/New Zealand Technical Report is an identical adoption of the IEC publication IEC/TR 61000-3-6, Ed 2.0 (2008). The guideline is also intended to serve as a supporting document to the National Electricity Rules and other jurisdictional technical electricity rules.