In recent years, the study of sensor and robot networks for ambient assisted living applications has gained a growing attention. In this work, a multimodal user interface for a distributed ambient intelligence architecture is presented. The user interface has been designed with in mind the specific characteristics of each user and the easiness of use of functions even for people without familiarity with technology. The system has been tested with elderly users: the acquired experience allows the analysis of problems such as user acceptance, usability and suitability of these systems. The tests have shown a good users' feeling towards the interface, especially in relation to the voice interface.