Cooperative Educational Service Agencies are intermediate service agencies that provide programs, services, and resources to a region of school districts in the state of Wisconsin. This dataset was assembled using county-derived school district boundary data and school district information from the Department of Public Instruction website. Each year, there is a chance for reorganizations to take place that either transfer territory between school districts or consolidate/dissolve/create districts. These reorganizations go into effect on July 1st of each year. Sometimes reorganizations involve CESA boundaries as territory transfers between school districts located in two different CESAs. In 2019, there were no reorganizations that caused changes to CESA boundaries.Version 2.0 and all versions from 2017 contain an error where the Mount Horeb Area School District was attributed to CESA 3 instead of 2. This error was corrected in version 2.1 and is correct in all layers since.