  We compute the planar part of the two-loop five gluon amplitude with all
helicities positive. To perform the calculation we develop a D-dimensional
generalized unitarity procedure allowing us to reconstruct the amplitude by
cutting into products of six-dimensional trees. We find a compact form for the
integrand which only requires topologies with six or more propagators. We
perform cross checks of the universal infra-red structure using numerical
integration techniques.
