  We compute all helicity amplitudes for the scattering of five partons in
two-loop QCD in all the relevant flavor configurations, retaining all
contributing color structures. We employ tensor projection to obtain helicity
amplitudes in the 't Hooft-Veltman scheme starting from a set of primitive
amplitudes. Our analytic results are expressed in terms of massless pentagon
functions, and are easy to evaluate numerically. These amplitudes provide
important input to investigations of collinear-factorization breaking and to
studies of the multi-Regge kinematics regime.
