  The Be phenomenon, i.e. the ejection of matter from Be stars into a
circumstellar disk, has been a long lasting mystery. In the last few years, the
CoRoT satellite brought clear evidence that Be outbursts are directly
correlated to pulsations and rapid rotation. In particular the stochastic
excitation of gravito-inertial modes, such as those detected by CoRoT in the
hot Be star HD 51452, is enhanced thanks to rapid rotation. These waves
increase the transport of angular momentum and help to bring the already rapid
stellar rotation to its critical value at the surface, allowing the star to
eject material. Below we summarize the recent observational and theoretical
findings and describe the new picture of the Be phenomenon which arose from
these results.
