New Zealand has committed to reducing carbon emissions and working with other countries to avert the worst impacts of climate change. How the country intends to do this is not clear. The Climate Change Commission has produced some advice to government, but the advice misses a key point. A climate-friendly economy has to be efficient: it has to use resources and energy efficiently. New Zealand has a poor track record of improving its efficiency, as seen in its low productivity growth. To deal with the climate change challenge, New Zealand has to deal with its productivity challenge. This document provides some examples of how this can be achieved.