  The total systematic uncertainty of the neutrino flux in accelerator-based
neutrino experiments is dominated by the Monte Carlo modeling of hadronic
interactions. Direct hadron production measurements for T2K and Fermilab
neutrino experiments, MINERvA, NOvA and DUNE, are being performed at the
NA61/SHINE spectrometer at CERN's Super Proton Synchrotron. Crucial for
improving neutrino flux predictions, hadron yields, inelastic and production
cross sections are obtained at NA61/SHINE where interactions of various hadron
beams with thin and thick (replica) targets are reproduced. Recently obtained
results will be reported. An extension of NA61/SHINE's programme of hadron
production measurements for neutrino experiments is planned beyond 2020.
