The heavy-ion collisions at RHIC and at the LHC are interpreted in the frame of hydrodynamic models. In particular the soft particle production is showing strong signatures of collective behavior. It was usually assumed that such behavior will not be observed in small systems such as proton-proton and proton-nucleus. Recent data from p-Pb collisions at the LHC have shown interesting signatures of collective behavior, especially in collisions that produce large final-state particle multiplicities. We examine these signatures, compare them to similar results in pp and heavy-ion collisions and discuss the possibility that a collective system is produced in these systems.