In this paper we present a concise analysis of the requirements for effective action selection, and a centralized action selection model that fulfills most of these requirements. In this model, action selection occurs by combining sensory information from the non-homogenous sensors of an off-the-shelf robot with the feedback from competing behavioral modules. In order to successfully clean an arena, the animal robot (animat) has to present a coherent overall behavior pattern for both appropriate selection and termination of a selected behavior type. In the same way, an animat set in a chasing task has to present opportunist action selection to locate the nearest target. In consequence, both an appropriate switching of behavior patterns and a coherent overall behavior pattern are necessary for effective action selection.