This document provides an overview of the CAS (Central Authentication Service) and Shibboleth identity management systems. It describes CAS as an open source single sign-on system that allows web applications to avoid storing user passwords by redirecting authentication to a central service. Shibboleth is described as enterprise federated identity software based on SAML standards that allows secure sharing of user attributes between identity providers and service providers across security domains. The document also summarizes Unicon's consulting services for implementing and customizing CAS and Shibboleth identity solutions.