  Guided by the large-Nc limit of QCD, we construct the most general chiral
resonance Lagrangian that can generate chiral low-energy constants up to
O(p^6). By integrating out the resonance fields, the low-energy constants are
parametrized in terms of resonance masses and couplings. Information on those
couplings and on the low-energy constants can be extracted by analysing QCD
Green functions of currents both for large and small momenta. The chiral
resonance theory generates Green functions that interpolate between QCD and
chiral perturbation theory. As specific examples we consider the VAP and SPP
Green functions.
