  We study the behaviour of time evolved quantum mechanical expectation values
in Lagrangian states in the limit $\hbar\to 0$ and $t\to\infty$. We show that
it depends strongly on the dynamical properties of the corresponding classical
system. If the classical system is strongly chaotic, i.e. Anosov, then the
expectation values tend to a universal limit. This can be viewed as an analogue
of mixing in the classical system. If the classical system is integrable, then
the expectation values need not converge, and if they converge their limit
depends on the initial state. An additional difference occurs in the timescales
for which we can prove this behaviour, in the chaotic case we get up to
Ehrenfest time, $t\sim \ln(1/\hbar)$, whereas for integrable system we have a
much larger time range.
