Server and Tools revenue increased in both product sales and Enterprise Services. Product revenue increased $347 million or 9%, driven primarily by growth in SQL Server, Windows Server, and System Center, reflecting continued adoption of the Windows platform. Enterprise Services revenue grew $102 million or 10%, due to growth in both Premier product support and consulting services.
Server and Tools operating income increased, primarily due to revenue growth, offset in part by higher cost of revenue and sales and marketing expenses. Cost of revenue increased $163 million or 17%, primarily reflecting higher headcount-related expenses. Sales and marketing expenses grew $76 million or 7%, reflecting increased fees paid to third-party enterprise software advisors and corporate sales and marketing activities.