SuperLEAR is the ideal machine to make connection between boson exchange theory models working at low energy (LEAR) and the fundamental QCD approach at higher energy. To illustrate that we will show what has been done so far in polarization in the momentum range including LEAR and SuperLEAR and insist on the open problems which SuperLEAR could address. We shall start with a review of polarization results up to ∼ 15 GeV/c in different channels, concentrating on the spin observables, then make a brief status on the availability of polarized antiprotons or antineutrons, and end with a few open problems which SuperLEAR can help solving.