The correlation between baryon number and strangeness elucidates the nature of strongly interacting matter, such as that formed transiently in high-energy nuclear collisions. This diagnostic can be extracted theoretically from lattice QCD calculations and experimentally from event-by-event fluctuations. The analysis of present lattice results above the critical temperature severely limits the presence of $q\bar q$ bound states, thus supporting a picture of independent (quasi)quarks. Higher order correlations as extracted from Lattice QCD will also be discussed. We will argue that an effective mean field description might be appropriate for the matter at high temperature. The consequences for observables such as flow will be discussed.