In recent years, a number of countries have adopted versions of the 'Australian' electoral system of preferential voting for both national and sub-national elections. This article examines the diffusion of preferential voting systems around the world. It distinguishes between various types of preferential voting manifested in both majoritarian (eg alternative vote) and proportional (eg single transferable vote) contexts. It then examines the empirical record of the adoption of preferential voting in Europe, North America and the Pacific, identifying three ways in which the 'Australian' system has been transferred to other countries, via colonial transplanting, international imitation, and normative appeal. While the first two approaches have been traditionally influential, in recent years the normative appeal of preferential voting systems has become paramount. This is in part because of the globalisation of electoral assistance, which has provided an important opportunity for the diffusion of what have been, until recently, distinctively 'Australian' electoral procedures.