|This article relies on references to primary sources. (January 2008)|
Congresspedia was a wiki that ran from April 2006 to March 2009, designed to hold information on the workings of the U.S. Congress. It was fully contained within SourceWatch, a larger wiki meant to document the people, organizations and issues shaping the public agenda. The Congresspedia portion of SourceWatch was publicly launched on April 26, 2006, with articles on each U.S. senator and U.S. representative. Congresspedia was a collaborative project of the Center for Media and Democracy and the Sunlight Foundation. In March 2009, the content of Congresspedia was moved to a wiki on the OpenCongress website, which is owned and funded by the Participatory Politics Foundation and the Sunlight Foundation. The last editor of Congresspedia was Conor Kenny, who currently runs the corresponding OpenCongress wiki.
The purpose of Congresspedia was to give citizens and media the ability to root out corruption and bring transparency to the system.  It was based on a set of basic ideas:
- A well-informed public is an essential ingredient of a healthy democracy.
- Most people feel they are not being well represented in Washington, while lobby groups and other special interests are. Despite this fact, however, most citizens could not name the specific interest groups that support and lobby their own representatives.
- The cost of winning election to Congress has become so expensive that most members raise funds year-round and work hard to maintain good relations not just with their constituents back home, but also with the "cash constituents" who supply the money for their campaigns. Everyone needs to know who these cash constituents are.
- Despite the constant flow of news from Washington D.C., much of what happens in the halls of Congress is not widely known outside of the nation's capital – and plenty of insiders like it that way.