On December 19th 2002 the accusatory system was formally introduced in the Colombian Constitution. This is, perhaps, the most complex change that our judicial system has undergone in the last decade. The implementation of the new criminal system implied a profound change in several institutions: a) the criminal courts, b) the general prosecution office; c) the national defense office; and d) all other state agencies that support criminal investigations. In order to design this transition the Comisión Interinstitucional para la Implantación del Sistema Penal Acusatorio (a governmental Commission responsible for the implementation of the accusatory system) open up a bidding. Uniandes in a temporal Union with the Instituto SER de Investigación, won this call for tenders. This paper briefly describes the way this multidisciplinary effort was done under the direction of the industrial engineering department.