Be stars are well known to be rapid rotator and to show intermittent emission-line activity. Such an activity is now interpreted as an abrupt mass-ejection and formation of a cool disk in the equatorial region and then its gradual disappearance mass-loss is called as episodic mass-loss.

Rapid rotation and mass-loss connection in Be stars was suggested for the first time by struve(1931), which necessarily leads to the requirement of break-up velocity in Be stars. However, Vsin i statistics suggests almost all Be stars are well below the break-up velocity. The additional forces have been searched for so far; i.e., stellar wind, magnetic field, mass accretion, and so on. At the moment, none of them can succeed in explaining the episodic mass-loss in Be stars.