What began as a small group of library systems in mid-2000, quickly grew to include all the public library systems in the state of Wisconsin, almost doubling the original number of partners. Partners are assessed annual dues to sustain the organization and fund new and continuing projects. WPLC is governed by the WPLC Board which includes a representative from each partner. 
- Bridges Library System
- IFLS Library System
- Kenosha County Library System
- Manitowoc-Calumet Library System
- Milwaukee County Federated Library System
- Monarch Library System
- Nicolet Federated Library System
- Northern Waters Library Service
- Outagamie-Waupaca Library System
- Prairie Lakes Library System
- South Central Library System
- Southwest Wisconsin Library System
- Winding Rivers Library System
- Winnefox Library System
- Wisconsin Valley Library Service