Central Authentication Service (CAS) is an open-source Apache v2 project on GitHub, under the sponsorship of the Apereo foundation. CAS attempts to provide an enterprise-ready multilingual authentication platform for the web. This session attempts to provide an overview of the CAS open-source software, its role in the identity and access management space and the problems/solutions it addresses. We will also touch upon system features, deployment strategies, authentication protocols (CAS, OIDC, SAML2, etc) and application integration techniques that are made in the latest available release. Attendees will gain an understanding of the CAS ecosystem and may be encouraged to adopt and deploy it to fulfill their own IAM/SSO needs.