1996A&A...308..290P

Millisecond pulsars have an outstandingly regular period of rotation, which has led to exciting results and opens great perspectives in cosmology, gravitation and the physics of neutron stars, as well as in astrometry and solar system dynamics. Also this stability suggests several approaches for the development of a time scale from pulsar observations. We review the different relations between pulsars and time scales and estimate the intrinsic stability of each. We show how atomic time can benefit from an ensemble pulsar time and how such an ensemble may presently reveal some long term instabilities in atomic time. Finally the observations of a pulsar in a binary system allow to generate a binary pulsar time, which is the most accurate astronomical time scale.