He has done outstanding work on the history of economic development and infant industry protectionism:
Kicking Away the Ladder: Development Strategy in Historical Perspective, London, 2002.Ha-Joon Chang demonstrates that many Western nations industrialized through infant industry protectionism. It is a complete myth that industrial development occurred through free trade and free markets in many Western countries.
Bad Samaritans: Rich Nations, Poor Policies, and the Threat to the Developing World, London, 2007.
This is a very interesting talk about his new book, 23 Things they Don’t Tell You about Capitalism (Allen Lane, London 2010).