Microsoft System Center Essentials 2007 is a new management solution in the System Center family of IT systems management products specifically designed for midsize businesses (up to 500 PCs and 30 Servers). Essentials 2007 provides a unified management solution that enables IT professionals in midsize organizations to proactively manage their IT environment with increased efficiency. Licensing: This Server Management License (ML) must be purchased in conjunction with Essentials 2007 Server License. This provides management of one additional Windows-based server operating system environment. This Server ML comes with Microsoft's maintenance plan, Software Assurance (SA).