The Northeast Kansas Library System's filtering project started out as a response to the passage of CIPA, the Children's Internet Protection Act, in January 2001. Originally called "onGuard," it was a service that the Northeast Kansas Library System created for its members. When the Supreme Court ruling did uphold the constitutionality of the CIPA, the Kansas State Library became interested in expanding their filtering system to all public libraries in Kansas. Today, "Kanguard" is a statewide Internet content filter that's provided as a service of the Kansas State Library. In this article, the author describes how this collaborative, far-reaching filter works.