Understanding the internal components of Office Communications Server 2007 is essential for proper implementation planning and troubleshooting, and this chapter has provided an overview of the architecture and components of Microsoft Office Communications Server 2007. The Office Communications Server architecture was first described, including a description of pool configurations, component architecture, and enterprise pools. This was followed by a discussion of the internal components of Office Communications Server, including the core, presence, conferencing, and VoIP components of the platform.