Multiparton Interactions, Small-x Processes and Diffraction

The connection between multiparton interaction, diffractive processes and saturation effects is discussed. The relation of the rise of the gluon density at small longitudinal momentum fractions x with the occurrence of saturation, diffraction and multiparton interaction is being studied both experimentally and theoretically. We illustrate key ideas underlying recent progress, and stress the role of different theoretical approaches to small-x QCD evolution in investigations of multiparton interactions.