Firstly, a prototype for implementing computer-assisted music improvisation will be produced. This prototype will extend existing work on IRMS (the Continuator) to allow more systematic and educational experiments to be performed. An extension of the existing music learning module will be designed to allow the handling of external (contextual) information in IRMS. In particular, the target will be able to add harmonic and rhythmical constraints to the basic Continuator-like system. This will be done by developing specific "rectifiers", which will be designed as plugins to allow many possible configurations. We will also study ways of reducing the amount of hardware needed in formal context with several children, for instance by considering cheap and robust hardware. Finally, modules will be developed to implement the IRMS concept in the context of musical performance, notably collaborative music improvisation. The main target here is to allow users to easily change their "interaction mode" during the improvisation. To this aim, a reflexive architecture will be developed, in which interaction modes will be reified (i.e. represented explicitly) to be easily manipulated by the software.