  The large luminosity and the increased kinematical domain accessible at the
LHC will allow to isolate large numbers of events with multiple parton
collisions. Interestingly, the hadron is probed in different points
contemporarily in the process, which allows to obtain information on the
correlations between partons in the hadron structure. The whole experimentally
accessible information on multiple parton collisions consists in the
probability distribution of the elementary interactions, while the inclusive
cross sections, usually considered in large p_t processes, acquire a precise
statistical meaning as moments of the multiplicity distribution. Conversely
different and more "exclusive" cross sections become experimentally viable,
providing complementary information on the interaction dynamics. The matter is
discussed in details in the case of hadron-hadron collisions and the role of
parton correlations is outlined both in the inclusive and in the "exclusive"
cross sections.
