ABSTRACT
By nature heavy-ion collisions are truly dynamical processes. In the nucleonic regime, a sizeable fraction of collisions leads to the formation of a, possibly shortlived, composite which exhibits patterns of a more or less thermally equilibrated object. The question of the degree of thermalization attained in such collisions actually turns out to constitute one of the major open questions in the field (see also chapter 8). A key aspect is thus to access and possibly analyse the behaviour of the system before equilibration. It turns out that such studies provide valuable clues on the dynamics of the collision as a whole, and on the way to equilibrium. This is what we discuss in this chapter.
