There seems to be a bug somewhere in #include <boost/algorithm/string.hpp> If I am not mistaken, this is the central include file for all the string algorithms. But if, e.g. in replace_example.hpp, you replace the separate declarations of #include <boost/algorithm/string/replace.hpp> #include <boost/algorithm/string/erase.hpp> #include <boost/algorithm/string/case_conv.hpp> with //#include <boost/algorithm/string/replace.hpp> //#include <boost/algorithm/string/erase.hpp> //#include <boost/algorithm/string/case_conv.hpp> #include <boost/algorithm/string.hpp> the file no longer compiles. However, #include <boost/algorithm/string/replace.hpp> //#include <boost/algorithm/string/erase.hpp> //#include <boost/algorithm/string/case_conv.hpp> #include <boost/algorithm/string.hpp> does work. Is there an error in the order of header inclusion? Leo Goodstadt