  Multiple Partonic Interactions are often crucial for interpreting results
obtained at the Large Hadron Collider (LHC). The quest for a sound
understanding of the dynamics behind MPI - particularly at this time when the
LHC is due to start its "Run II" operations - has focused the aim of this
workshop. MPI@LHC2014 concentrated mainly on the phenomenology of LHC
measurements whilst keeping in perspective those results obtained at previous
hadron colliders. The workshop has also debated some of the state-of-the-art
theoretical considerations and the modeling of MPI in Monte Carlo event
generators. The topics debated in the workshop included: Phenomenology of MPI
processes and multiparton distributions; Considerations for the description of
MPI in Quantum Chromodynamics (QCD); Measuring multiple partonic interactions;
Experimental results on inelastic hadronic collisions: underlying event,
minimum bias, forward energy flow; Monte Carlo generator development and
tuning; Connections with low-x phenomena, diffraction, heavy-ion physics and
cosmic rays. In a total of 57 plenary talks the workshop covered a wide range
of experimental results, Monte Carlo development and tuning, phenomenology and
dedicated measurements of MPI which were produced with data from the LHC's Run
I. Recent progress of theoretical understanding of MPI in pp, pA and AA
collisions as well as the role of MPI in diffraction and small-x physics were
also covered. The workshop forstered close contact between the experimental and
theoretical communities. It provided a setting to discuss many of the different
aspects of MPI, eventually identifying them as a unifying concept between
apparently different lines of research and evaluating their impact on the LHC
physics programme.
