The StarTeam Agile Administrator can create server tags for stories that will be available for all projects within StarTeam Agile. This is a good way to ensure consistent tagging across projects within StarTeam Agile. This can be particularly important if you plan on utilizing the Info Stream feature to share stories across projects. Project Administrators can create project tags to meet their project's needs. 

Note: While story tags do not migrate when a story is shared between backlogs via Info Stream, having server tags will allow for consistent tagging across projects. You will need to reapply tags when a story is accepted into a new backlog.