SharePoint Records Management
The Records Management infrastructure of Microsoft Office SharePoint Server (MOSS) is designed to archive information no longer necessary in the daily running of the enterprise. The component is designed to ensure and protect the integrity of the content, register changes and authorization, ensure saved information is accessible only to authorized personal, and, most importantly, ensure that information cannot be altered or deleted. With Records Management, it is possible to block access at any point, if and when deemed necessary by the administrator.
See also "Records Management for Microsoft Office SharePoint Server" on SharePoint Briefing.com.