  Higher orders in perturbation theory require the calculation of Feynman
integrals at multiple loops. We report on an approach to systematically solve
Feynman integrals by means of symbolic summation and discuss the underlying
algorithms. Examples such as the non-planar vertex at two loops, or integrals
from the recent calculation of the three-loop QCD corrections to structure
functions in deep-inelastic scattering are given.
