Leading/nonleading Charm Hadroproduction in the Quark-Gluon String Model

Leading charm production in reaction ${\pi }^{-}N\to DX$ is discussed.Three experiments at Fermilab and CERN have measured a rather large enhancement in production rate of leading $D^{-}$-mesons over nonleading $D^{+}$.A good description of these results is obtained in Quark Gluon String Model (QGSM) if the idea of ‘intrinsic charm’ is involved. The weight of the $c\bar{c}$ pairs in the quark sea of colliding hadrons is estimated from the experimental data. The comparison with other theoretical models is also carried out.