This is the twenty-ninth edition of Reference Data Series No. 2, Nuclear Power Reactors in the World, which is published once per year, and presents the most recent reactor data available to the IAEA. It contains the following summarized information: General information as of the end of 2008 on power reactors operating or under construction, and shut down; and Performance data on reactors operating in the Agency’s Member States, as reported to the IAEA.