RXTEhas discovered a flurry of new accreting millisecond pulsars in the past two years, based on dedicated and all‐sky monitoring. How couldRXTEand an enhanced future timing mission capitalize on these successes? I argue that the major issues to tackle are binary orbit and spin evolution. There is enough potential uncertainty in the models that drive binary evolution that it is worth attempting to detect orbital period changes in millisecond pulars. WithRXTEit is possible to measure the orbital phase to within a few to a few hundred microperiods, and that can be improved by a factor of ∼ 3 with an enhanced timing mission with ∼10 times the collecting area. This in turn will make it possible to feasibly detect significant orbital period changes within a few years baseline. Neutron star spin torques due to accretion are also important, since they are presumably the mechanism by which low mass X‐ray binaries are spun up to millisecond pulsars in the first place. The current ambiguous data on spin torques suggests that further, more ambitious studies are required. I also discuss several other issues, such as pulse phased spectroscopy, which may improve our knowledge of the neutron star equation of state. I conclude with a brief presentation of the “ideal” millisecond pulsar observatory. © 2004 American Institute of Physics