We present a worldvolume effective action suitable for the study of the confined phase of a (Dp,Dp) system at weak coupling, and we identify the mechanism by which the fundamental string arises from this action when the Dp and theDp annihilate. We construct an explicit dual action, appropriate for the strong coupling regime, which realizes a generalized Higgs-Stückelberg phase for the (relative) (p-2)-form dual to the (overall) BI vector, the mechanism put forward by Yi and collaborators for realizing non-perturbatively the breaking of the overall U (1) g auge group. Our results provide an explicit realization of the perturbative breaking of the overall U (1) in a way that is consistent with the duality symmetries of String Theory.