Colombia is currently the world´s largest producer of coca leaf and the principal producer of opium poppies in the Americas; the plants are the basic raw materials used to produce cocaine and heroin. This document will analyze the current relationship between these crops and illegal armed groups in Colombia, using the hypothesis that the geographical intensification of the conflict is the principal cause of expanding illicit crop production. This relationship was analyzed using a theoretic model, in which an interaction between illegal armed activity and strategic territorial control lead to cocaine production. Spatial analysis techniques were then applied, especially spatial association indicators; and a clear spatial dynamic was observed, related to the two aspects mentioned above. Non parametric exercises were also carried out using matching estimators, to determine the effect illegal armed groups have on coca crops, and also to analyze the efficiency of aerial eradication policies. The results suggest that a large percentage of coca production in Colombia is due to the effects of illegal armed activity. We therefore conclude that the expansion of illegal crop growing is a consequence of the expanding conflict. In contrast, coca crops can only be used to explain a small part of the armed conflict in Colombia. In addition, we found that crop eradication via aerial spraying has not been an efficient tool in the fight against coca production in the country.