  Systematic studies on the production of strange hyperons and the phi meson as
a function of beam energy and system size performed by the NA49 collaboration
are discussed. Hadronic transport models fail to describe the production of
multi strange particles (Xi, Omega), while statistical models are generally in
good agreement to the measured particle yields at all energies. The system size
dependence is well reproduced by the core-corona approach. New data on K*(892)
production are presented. The yields of these short-lived resonances are
significantly below the statistical model expectation. This is in line with the
interpretation that the measurable yields are reduced due to rescattering of
their decay products inside the fireball.
