2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/42941Recent progress in understanding the strong physics regime of QCD is described. The role played by condensates, particularly $<q{\bar q} >$, in breaking chiral symmetry and generating constituent masses for $u$ and $d$ quarks is reviewed. The influence this has on hadrons with vacuum quantum numbers is emphasised. What we know of this sector from recent experiments on $ϕ$-radiative decays and from $D$ decays to light hadrons is discussed. How we may gain a more complete understanding of this vacuum sector is outlined.8 pages, 12 figures. Talk at the International Workshop on QCD: QCD@Work 2003 -Conversano (Italy) 14-18 June 2003 (eConf C030614)High Energy Physics - Phenomenologytext