This thesis proposal suggests a model-based approach to obtain, from a set of behavioural scenarios of a given reactive software system, a graphical animation for reproducing that set of scenarios for validation purposes. The approach assumes that the requirements of the system are described by a use case diagram, being the behaviour of each use case detailed by a collection of scenario descriptions. These use cases and scenarios are transformed into a Coloured Petri Net (CPN) model, which is next complemented with animation-specific elements. By executing the CPN model, it is possible to animate the scenarios in a user-friendly way and thus ensuring an effective involvement of the users in the system’s validation. The CPN model is enforced to be (1) parametric, allowing an easy modification of the initial conditions of the scenarios, (2) environment-descriptive, meaning that it includes the state of the relevant elements of the environment, and (3) animation-separated, implying that the elements related to animation are clearly separated from the other ones. We validate our approach based on its application to two examples of reactive systems.