  We discuss expectations of saturation physics for various observables in
heavy ion collisions. We show how simple saturation-inspired assumptions about
particle production in heavy ion collisions lead to Kharzeev-Levin-Nardi model.
Comparing this model to RHIC data on particle multiplicities we conclude that
saturation effects may play an important role in particle production and
dynamics at the early stages of Au-Au collisions already at RHIC energies. We
then estimate the contribution of the initial state two-particle azimuthal
correlations to elliptic flow observable v_2 in Au-Au collisions by
constructing a lower bound on these non-flow effects based on v_2 obtained from
the analysis of proton-proton (pp) collisions.
