This document summarizes outcomes from an interoperability experiment on using Shibboleth for access management of geospatial web services. It discusses how Shibboleth can allow single sign-on access to protected spatial data resources across administrative domains. The academic sector helped test and demonstrate modified open source clients that work with Shibboleth-secured services to improve access for research and education. Going forward, expanding the use of Shibboleth and strengthening connections between access management federations could maximize the benefits.