  We present a covariant approach to describe the low--lying scalar,
pseudoscalar, vector and axialvector mesons as quark--antiquark bound
states.This approach is based on an effective interaction modeling of the
non--perturbative structure of the gluon propagator that enters the quark
Schwinger--Dyson and meson Bethe--Salpeter equations. We extract the meson
masses and compute the pion and kaon decay constants. We obtain a
quantitatively correct description for pions, kaons and vector mesons while the
calculated spectra of scalar and axialvector mesons suggest that their
structure is more complex than being quark--antiquark bound states.
