  We take advantage of interferometric measurements of Achernar to inquire on
its internal rotational law. The reinterpretation of interferome-tric data and
the use of fundamental parameters corrected for gravitational darkening effects
and models of 2D-models of internal stellar structures, lead us to the
conclusion that the star could not be a rigid, near critical, rotator but a
differential rotator with the core rotating $\sim3$ times faster than the
surface.
