The Resource Sharing Alliance is a non-profit network of 190 library agencies, including public libraries as well as public and private academic libraries, and special schools. Working together, these libraries serve the population of twenty-six contiguous counties in Illinois, using CARL Systems software and Tandem hardware.

The RSA has been in existence since 1980 and merged with the Alliance Library System in July of 1999. The Resource Sharing Alliance is centrally located to its membership at 600 High Point Lane in East Peoria. The Resource Sharing Alliance serves as the LLSAP (Local Library System Automation Program) for the Alliance Library System.