From Quality Software Components:
Team Coherence provides an extensive feature set designed to save time and money through reliable source code control. It enables development teams to automatically protect and track their most valuable source code, documentation, binaries, and all other file types as they change throughout the software life cycle. Versioning features, such as labels, provide snapshots of a project for the quick retrieval of any previous version in the software life cycle.
Support for promotion levels allows you to say with certainty that all files have been through the various development and testing stages by the time they are released to end users. The ability to share files across projects promotes the reuse of code and components across projects and simplify code maintenance by propagating changes across all shared whenever a file is updated. Support for both Parallel and Serial development modes, or a combination of both, allows you to decide which methodology suits you best, not the other way around.