  A two-component model is developed for diffractive electroproduction of
$\rho^0$, $\phi$ and $\jpsi$, based on non-perturbative and perturbative
two-gluon exchange. This provides a common kinematical structure for
non-perturbative and perturbative effects, and allows the role of the
vector-meson vertex functions to be explored independently of the production
dynamics. A good global description of the vector-meson data is obtained.
