Welcome to the Correlates of War (COW) project homepage. COW seeks to facilitate the collection, dissemination, and use of accurate and reliable quantitative data in international relations. Key principles of the project include a commitment to standard scientific principles of replication, data reliability, documentation, review, and the transparency of data collection procedures. More specifically, we are committed to the free public release of data sets to the research community, to release data in a timely manner after data collection is completed, to provide version numbers for data set and replication tracking, to provide appropriate dataset documentation, and to attempt to update, document, and distribute follow-on versions of datasets where possible. We intend to use our website as the center of our data distribution efforts, to serve as central site for collection of possible error information and questions, to provide a forum for interaction with users of Correlates of War data, and as a way for the international relations community to contribute to the continuing development of the project.