This work presents a new approach of control specification. Many researches on control synthesis sacrificed some requirement of control in order to satisfy control specifications that are expressed by a linear combination of place markings in a given reachability graph. However, these control specifications cannot usually fulfil some requirement of control; this is why we introduce a new approach based on admissible paths constraints and not on the combination of place markings. An application of this approach of control specification is implemented on a flexible manufacturing system (FMS) at ENIM (National School of Engineering of Metz) in France