Methods, systems, and computer program products are disclosed for sharing data related to a session created by a user within a domain of sites or services. A user logs on to a site, such as a Web site or other entity, and creates a session. The session created has an identifier which can be shared with other sites or entities in the same domain or logical group. In the course of utilizing services on the site, the user attempts access to services on another site. When this attempt is made, the user's session data is passed to the second site. The session data is analyzed on the second site by checking configuration data on the second site. If it is not found to be valid (e.g. it is created by a site outside the domain of the second site), the user is required to explicilty logon. If the configuration data indicates that it is valid, the session data is passed back to the first site using a verification routine (part of the configuration data) on the second site. If the first site authenticates the session data, the user is allowed to access services on the second site without having to explicitly logon.