  This talk is devoted to review the field of strangeness production in
(ultra-)relativistic heavy ion collisions within our present theoretical
understanding. Historically there have been (at least) three major ideas for
the interest in the production of strange hadronic particles: (1) mass
modification of the kaons in a (baryon-)dense environment; (2) (early) K+ -
production probes the nuclear equation of state (EoS); (3) enhanced strangeness
production especially in the (multi-)strange (anti-)baryon channels as a signal
of quark gluon plasma (QGP) formation. As a guideline for the discussion I
employ the extensive experience with microscopic hadronic transport models. In
addition, I elaborate on the recent idea of antihyperon production solely by
means of multi-mesonic fusion-type reactions.
