Hi there, Here attached is a small example of the new design the timer library is more or less likely to follow, however while doing it it raised a number of concern to me : About the device class, the original drafts says it contains only two member functions, start() and elapsed(). I think it lacks obvious others like reset(), or something that tells it to stop and start again. Should the device be allowed to start with an duration offset ? Should it be allowed to be started automatically ? Why doesn't boost::date_time::microsec_clock and similar class typedef the time_type ? Because of this I'm forced to do a ptime_device when I could have done a date_time_device. I'm able to get around this but I think it'd require partial template specialization or worse two device classes for things that have the same interface. I think we'd agree on the device class member functions first, and once done we can then move on about how the timer class member functions should be :) Philippe