I am using boost in the build of a commercial software package using Microsoft Visual Studio 2008 as the primary build engine. We are building for both 32- and 64-bit targets. There is no mention in the "getting started" documents of how to build the libraries for different bitnesses. In the VS2008 world the build control files are parameterized with macros, the relevant one of which is $(PlatformName) which has the value "Win32" in 32-bit builds and "x64" in 64-bit builds. To permit maximally "clean" configuration control in the client code tree, the boost libs should live in directories with names based on this convention. I have manually created lib-Win32 and lib-x64 under the prior release and am in the process of doing the same under RC2. The purpose of this note is to suggest that there is probably a large audience of similarly situated folks who could use at least a breadcrumb in the documentation and, perhaps, some automation. The "installer" for windows should, in my opinion, use the ROOT_DIR/lib-$(PlatformName) convention as well.