Work-in-progress for the Boost.Chrono library has been added to the sandbox. See http://svn.boost.org/svn/boost/sandbox/chrono This work is in a very preliminary state. The only testing has been with VC++ 9.0 on XP-64 and a tiny bit on Ubuntu 8.04 Linux. There has been no work done yet on C++0x headers. The Jamfiles are there, but haven't been tested; I've been developing using the provided VC++ solution. The implementation of the clocks is going to be very system specific. If anyone would like to try .../libs/chrono/example/await_keystroke.cpp and report whether or not it compiles and works on their system, it would be appreciated. Patches to make .../libs/chrono/src/chrono.cpp work for various operating systems would be even more appreciated! I'm still unsure about even some of the basics, such as how to partition the three parts for boost. Are the time utilities, the compile-time rational arithmetic, and the type trait common_type three boost libraries, one boost library, or three parts of a larger boost library? There was some discussion of this in a prior thread, but I thought having the actual code available might move the discussion forward. There is a tiny bit of documentation; see .../libs/chrono/doc/index.html. Comments welcome! --Beman