  Strangeness enhancement (SE) in heavy ion collisions can be understood in the
statistical model on the basis of canonical suppression. In this formulation,SE
is a consequence of the transition from canonical to the asymptotic grand
canonical limit and is predicted to be a decreasing function of collision
energy. This model predictions are consistent with the recent NA49 data on
$\Lambda$ enhancement at $p_{lab}=40, 80, 158$ GeV.
