  Aiming at the calculation of the properties of rho-mesons, non-perturbative
QCD-based methods are discussed concerning their potentials as well as their
short-comings. The latter are overcome by combining these techniques. The
utilized methods are (i) the chiral constituent quark model deduced from the
instanton vacuum model and large-N_c arguments, (ii) chiral perturbation theory
unitarized by the inverse amplitude method and (iii) QCD sum rules. Advantages
of the combination of these methods are especially the absence of un-physical
quark-production thresholds and parameter-free results. Already in the chiral
limit and in leading order in 1/N_c one obtains a reasonable result for the
mass of the rho-meson, namely m_rho = 790 \pm 30 MeV. Using the KSFR relation
the universality of the rho-meson coupling is recovered. The latter is found to
be g = 6.0 \pm 0.3.
