The Little Bang: Searching for quark-gluon matter in relativistic heavy-ion collisions

I review the status of the search for quark-gluon plasma in relativistic heavy-ion collisions. The available data provide strong evidence for the "three pillars of the Little Bang model": strong radial expansion of the collision fireball with Hubble-like scaling, thermal hadron emission and primordial hadrosynthesis. It is argued that the initial state of the reaction zone exhibits features which cannot be understood with conventional hadronic dynamics, but are consistent with the formation of deconfined quark-gluon matter.