Infrastructure networks (e.g. transport, water, energy, telecommunications) support life and the economy of communities of all sizes. New Zealand has witnessed several damaging earthquakes in the last decade that provide a compelling case to accelerate building resilient infrastructures in the country, so we can minimize any adverse impacts from future earthquakes. One of the regions that is highly vulnerable to earthquakes is Wellington. With the region’s population continually expanding and placing increased demands on its ageing infrastructures, with limited redundancy in the networks, and with many of its assets close to and / or intersecting fault lines, a large earthquake in the region could be highly disruptive, potentially resulting in serious social and economic consequences. While it may not be possible to completely avoid the impacts, they can be reduced. This paper provides an overview of the process taken in delivering a Wellington Lifelines Group report that demonstrates how impacts from a future major earthquake can be reduced through integrated and targeted infrastructure resilience investments. To quantify the benefits that can be achieved by making the proposed investments, impact modelling on nine different lifeline utilities in the Wellington metropolitan area were conducted; the assessment approach taken, and results derived and their use to prioritise resilience investments, are shown in this paper for selected key networks. The time-stamped service outage maps and tables produced from this work formed an essential input to evaluate and demonstrate the impact of the proposed resilience initiatives on the regional and national economies.