  A selection of recent data referring to Pb+Pb collisions at the SPS CERN
energy of 158 GeV per nucleon is presented which might describe the state of
highly excited strongly interacting matter both above and below the
deconfinement to hadronization (phase) transition predicted by lattice QCD. A
tentative picture emerges in which a partonic state is indeed formed in central
Pb+Pb collisions which hadronizes at about T = 185 MeV, and expands its volume
more than tenfold, cooling to about 120 MeV before hadronic collisions cease.
We suggest further that all SPS collisions, from central S+S onward, reach that
partonic phase, the maximum energy density increasing with more massive
collision systems.
