I have finally decided to get my feet wet, when it comes to the 64-bit world. Honestly, all my fears turned out to be valid, and then some. I have a MSVS-2010 Solution that includes several varied projects: GUI, libraries (both kids) and Shell Extensions. Since a couple of my projects depend on Boost (the greatest set of libraries ever known to man! Boost rocks! Boost rules!!... but I digress): I decided to start there. Since I am getting some boost-related error messages, I figure that step number zero is to make sure that my Boost installation is healthy. This is how I build it: .\bootstrap.bat .\bjam.exe --with-date_time --with-filesystem --with-regex --with-system --stagedir=. --build-type=complete toolset=msvc-10.0 address-model=64 Notice that the above commands have served me well for years (minus the last parameter, which I am now using for the first time). Is that all I need? TIA, -Ramon