The twentieth century has witnessed a remarkable rise in armed conflicts that are most likely to occur in a weak state as well as a poor country. Furthermore, the rise of “new” non-state actors such as, organized criminal gangs, religious groups, mercenaries, ethnic militias and private security companies are widely recognized. ‘New War’ involves an apparent blurring of the boundaries among struggle for economic and political ends (war) and the force used for private material gain (criminal violence). In the light of the criminal motivations, the civil war in Sierra Leone (1991-2002) is an example of a recent complex conflict, amenable to both grievance and greed-based explanation. My position is that, although the violence is in part a reaction to political repression, the drive to possess the country’s valuable resource of diamond explains more convincingly the conflict. In this paper, I will argue that the greed theory is more convincing than the grievance theory in this period of “new wars”.