The crime of genocide, as one of the most complex crimes ever to be examined and prosecuted, is often referred to as the “crime of crimes.” It is never the result of a tragic accident, but always a deliberate, conscious, and intentional act. It is never a single act, but a collection of acts committed by a number of people acting in consort. Several elements of genocide prescribed by the Convention on the Prevention and Punishment of the Crime of Genocide (1948) distinguish it from other core crimes. The first one is the intention to destroy a protected group – the very specific intention that brings into question the core existence of the group itself. The second element is the focus of the perpetrator’s intent on a particular group ; his intent on destruction has to be directed against a national, ethnical, racial, or religious group. No other groups are included on that list. Given the significance to the protected group, this paper will focus on some important issues relating to the protected groups and their identifications, both in legal theory and jurisprudence of international courts. It will also cover some considerations on the exclusion of some other groups that are left unprotected from genocide.