Mexico provides one of the most important contemporary case studies for understanding criminal drug gangs and organized drug-trafficking organizations (DTOs). The country's criminal landscape has changed substantially over the past several decades: groups historically centred on trafficking illicit drugs have fragmented, diversified into multiple criminal markets, developed flexible networks, and competed over territory and access to legitimate economic and political structures. This transformation has been accompanied by severe violence, corruption, displacement, extortion, and institutional stress. Research suggests that violence cannot be explained by drug trafficking alone. Organizational fragmentation, competition among criminal groups, state enforcement strategies, local political economies, weak institutions, firearms availability, and the interaction between transnational drug markets and domestic criminal opportunities all contribute to observed patterns. The Mexican experience also illustrates a central paradox of enforcement: targeting senior criminal leaders can temporarily disrupt organizations but may, under some conditions, accelerate fragmentation and conflict among successor factions. This narrative review examines criminal drug gangs in Mexico as a socio-political and economic phenomenon rather than providing operational guidance for criminal activity. It reviews the historical evolution of Mexican DTOs, organizational structures, criminal-market diversification, violence and territorial control, corruption and governance, socioeconomic effects, state responses, international cooperation, and prevention strategies. Particular attention is given to the shift from relatively hierarchical trafficking organizations toward fragmented and networked forms of organized crime. The review argues that effective policy requires more than drug interdiction or leadership targeting: it requires strengthening justice institutions, reducing corruption, disrupting illicit financial flows, protecting communities, reducing recruitment opportunities, improving local governance, and addressing the transnational nature of firearms and drug markets.
Keywords:organized crime; drug trafficking organizations; criminal gangs; Mexico; cartels; violence; corruption; governance