  We summarize new pQCD results on pion production in proton-proton (pp),
proton-nucleus (pA) and nucleus-nucleus (AA) collisions. Our calculation
introduces intrinsic parton transverse momentum (k_T) and is performed
effectively at next-to-leading order (NLO), applying a K factor extracted for
jet events. Two different factorization scales, Q=p_{T,jet}/2 and p_{T,jet} are
used. Experimental data in pA collisions imply a preference for the latter
choice at NLO level. We display our results at CERN SPS for AA collisions.
