Optimal coordination of traffic signals requires proper activation of timing plans to match current traffic conditions. One of the greatest challenges in configuring a traffic responsive plan selection control mode is how to select only n number of timing plans (restricted by traffic controller memory limitations) to address possibly all traffic conditions/states that can be encountered in the field, for a specific site, but most importantly, how to associate each of these traffic conditions to one of the n timing plans stored in the traffic controller. This paper uses a multiobjective non-dominated sorting genetic algorithm to (1) select the best n timing plans to be stored in the controller and (2) group traffic states into m number of clusters, and associate each of the m clusters with one of the stored timing plans. A new performance measure, degree of detachment, developed by the writers to address the clustering requirements, is described in this paper.