It is often said that one of the aims of comparative law is to help in the harmonisation of law, but the intellectual worlds of the comparatist and the harmonisation scholar rarely coincide. This is not surprising. "When law is internationalised it changes. It is denationalised, modernised and liberalised, sometimes intentionally, sometimes inadvertently." The aim of this article is to act as a modest bridge between the two worlds by exploring the landscape in which harmonisation of international commercial law takes place and, in particular, one of the most successful attempts, the Vienna Convention on the International Sale of Goods (CISG).