  The probabilistic study of effective interface models has been quite active
in recent years, with a particular emphasis on the effect of various external
potentials (wall, pinning potential, ...) leading to
localization/delocalization transitions. I review some of the results that have
been obtained. In particular, I discuss pinning by a local potential, entropic
repulsion and the (pre)wetting transition, both for models with continuous and
discrete heights.
