One recurring need that many firms face is that of moving or copying large Microsoft SharePoint document libraries from one site to another. These sites may be on the same SharePoint farm (e.g., between extranet sites), or from a staging to a production farm. There are several commercially available tools for handling such migrations, from vendors such as AvePoint and Metalogix, but those products can cost thousands of dollars and add significant complexity to your firm’s “technology stack.” In this article I’ll show you how to move a document library of any size with just a bit of .NET code using the Windows SharePoint Services SDK.