Based on an interdisciplinary synthesis of the literature in political science and social psychology, this chapter emphasises that the issue of identity is critical in the pursuit of peace. The chapter attempts to discuss dual identities, which in the case of Afghanistan allow for both singular identities and a new overarching identity (to be formed in the peace process). The question of how to transform conflicts peacefully is the common point of intersection between theory and practice in the field of peace studies. If conflict, as a never-ending phenomenon, can be transformed into a peaceful perspective, then peace has a chance of becoming permanent on the ground and in the minds. In this regard, the issue of identity occupies an important place in the context of sustainable peace. Because identity affects almost all peace processes in a heard or unheard tone. This chapter will examine the identity issues within the framework of Afghanistan over the social identity theory and the common in-group identity model. Using the example(s) of Afghanistan (in addition Northern Ireland and South Africa), this chapter argues that a new and inclusive identity that does not assimilate individual identities (dual identity) has the capacity to enable sustainable peace.