- The document summarizes a workshop about using Shibboleth federations to securely access spatial data infrastructure (SDI) resources through web services. - An interoperability experiment was conducted where several organizations modified their web service client software to work with Shibboleth single sign-on across administrative domains. - The experiment demonstrated that using Shibboleth to securely access web feature and map services through single sign-on is practical and does not require major software changes. This could help address interoperability barriers for cross-border applications needing to access protected spatial resources.