Hi, Before moving all the classes on Boost.Ratio from boost:: to boost::ratios:: I wanted to signal that Boost.Ratio follows the names on the C++0x standard and that these names where choosen to be used in the std context and that any class is prefixed by ratio_. If a specific ratios namespace were in their minds, I'm sure that they will not use the ratio_add<> but just add<>. Please let me know if I'm wrong here. typedef boost::ratios::ratio<1, 2> R1; typedef boost::ratios::ratio<1, 3> R2; typedef boost::ratios::add<R1, R2> R; If we put all of them in boost::ratios maybe the class names contains redundant information typedef boost::ratios::ratio<1, 2> R1; typedef boost::ratios::ratio<1, 3> R2; typedef boost::ratios::ratio_add<R1, R2> R; Do the Boost community agree with these names or is this one of the special cases that needs consideration? Best, Vicente