I noticed some discussion in threads about the worries that some people have with linking their application against boost and then needing a third party library that also links to a potentially different version of boost that might not be available to the in source form. Has any thought been given to changing the boost namespace declaration to include the version number, like this: namespace boost_1_35_0 { // boost libraries declared here }; #ifndef BOOST_NAMESPACE_ALIAS_DECLARED #define BOOST_NAMESPACE_ALIAS_DECLARED namespace boost = boost_1_35_0; #endif // BOOST_NAMESPACE_ALIAS_DECLARED This allows an application linked to boost 1.X+1.0 to also link to a third party library that privately uses boost 1.X.0 without causing ODR problems. Of course it doesn't help if the third party library exposes boost types in its interface. We could even go further and add another wrapper around the #ifndef/#endif above like this: #ifndef BOOST_NAKED_NAMESPACE #ifndef BOOST_NAMESPACE_ALIAS_DECLARED #define BOOST_NAMESPACE_ALIAS_DECLARED namespace boost = boost_1_35_0; #endif // BOOST_NAMESPACE_ALIAS_DECLARED #endif // BOOST_NAKED_NAMESPACE This allows an application to #define BOOST_NAKED_NAMESPACE and then use the versioned boost namespace directly. With care, it would be possible to write an application that used two versions of boost simultaneously, for example if that mythical third party library *did* expose boost types in its interface... -- Jon Biggar Floorboard Software jon@floorboard.com jon@biggar.org