: You do not need to install SP1 or SP2 beforehand; SP3 includes every public and security update released through September 2011.

: This release marked the transition of Office 2007 into its extended support phase, making it the "likely final" major service pack. Key Enhancements & Fixes

At its core, Service Pack 3 is a cumulative maintenance release designed to enhance security, stability, and compatibility.

For IT administrators, Exchange Server 2007 SP3 (released earlier in 2010) was equally vital.

: Improved handling of specialized calendars (like the Chinese New Year in Singapore) and fixed Unicode character display in error messages.

: It fixed an issue where documents with custom security filters wouldn't show up in search alerts correctly.