Developed as a collaborative effort between the Columbia University libraries and Columbia University Press with a grant from the Andrew W. Mellon Foundation, Columbia International Affairs Online (CIAO) is a comprehensive source for theory and research in international affairs. It publishes a wide range of scholarship from 1991 onward that includes working papers from university research institutes, occasional papers series from NGOs, foundation-funded research projects, proceedings from conferences, books, journals and policy briefs. In addition to a search engine, CIAO also allows browsing by type of material and, within each material type, by publisher or journal title. CIAO is also a source for teaching materials including original case studies written by international affairs experts, course packs of background readings for history and political science classes. All sections of CIAO are updated monthly. Essentially this database is available only through an affiliation, mostly paid by the subscribing institution (also individual subscriptions are accepted), with some basic material available free of charge. A quite sophisticated design and the site’s information density may prove intimidating for the average user.