  We sketch here an approach to the computation of generalised parton
distributions (GPDs), based upon a rainbow-ladder (RL) truncation of QCD's
Dyson-Schwinger equations and exemplified via the pion's valence dressed-quark
GPD, $H_\pi^{\rm v}(x,\xi,t)$. Our analysis focuses on the case of zero
skewness, $\xi=0$, and underlines that the impulse-approximation used hitherto
to define the pion's valence dressed-quark GPD is generally invalid owing to
omission of contributions from the gluons which bind dressed-quarks into the
pion. A simple correction enables us to identify a practicable improvement to
the approximation for $H_\pi^{\rm v}(x,0,t)$, expressed as the Radon transform
of a single amplitude. Therewith we obtain results for $H_\pi^{\rm v}(x,0,t)$
and the associated impact-parameter dependent distribution, $q_\pi^{\rm
v}(x,|\vec{b}_\perp|)$, which provide a qualitatively sound picture of the
pion's dressed-quark structure at an hadronic scale.
