  We discuss some key issues associated with duality-violating and
non-perturbative OPE contributions to the theoretical representations of light
quark current-current two-point functions and relevant to precision
determinations of alpha_s from hadronic tau decay and electroproduction
cross-section data. We demonstrate that analyses with an explicit
representation of duality-violating effects are required to bring theoretical
errors in such extractions under control, motivating the accompanying paper in
these proceedings, which presents the results of such an analysis.
