This paper presents the frrst results of the conception of a generic model of specifications. This model is based on knowledge acquisition and structuration from specifications folders of several automated people movers. The purpose of this research is to facilitate the transition between user's needs and the drawing up of software specifications. After having examined different standards in order to define quality criteria required for a specification, this research was carried on a real-world application, relevant in the field of transport systems: an automatic driving sub-system.