In this chapter, we have examined the new Business Intelligence capabilities available in SharePoint Server 2007 through Excel Services. We began with a discussion of how to configure Excel Services on servers where Office SharePoint Server 2007 has already been installed. We identified the basic steps required to enable Excel Services and to configure a Trusted File Location, which will allow workbooks to be processed on the server. Next we reviewed the roles of the major components of Excel Services-including Excel Calculation Services, Excel Web Access, Excel Web Services, and the Excel Calculation Service Proxy. We then explained how to publish workbooks through the Publish command in Excel 2007, including how to hide sheets and define parameters that affect the way users interact with the workbook. We then looked at the ways that users can work with workbook data through Excel Web Access and Web Access Web Parts. In the next section, we described ways to control security on workbooks accessed by Excel Services. We discussed performance considerations with Excel Web Services, including controlling the number of sessions and the timeout duration for each session. Finally, we looked at ways that workbooks can access external data sources from within Excel Services.