This chapter examines the changing nature of drug related violence in Mexico and provides a framework for an interpretation of the country's human rights crisis. Calderón's choice of anti-narcotics policy and drug enforcement played a key role in exacerbating criminal violence. The analysis provides some insights into the strengths and weaknesses of the main arguments that have been advanced to explain the violent crisis engulfing Mexico. It looks at the scale, character and nature of the violence that followed Calderon's massive deployment of troops, ostensibly to fight organised crime, as soon as he took power. During the Fox administration, criminal competition had led to full scale criminal wars in the major cities along the border, from Tijuana, to Juarez to Nuevo Laredo. For decades there had been concern within the security community about the detrimental effects of the headhunting 'kingpin' policy devised to eliminate the leaders of drug cartels.