Many everyday actions take place in a social and affective context and presuppose that the agents share this context. But current motion synthesis techniques, e.g. in computer graphics, mainly focus on physical factors. The role of other factors, and specifically psychological variables, is not yet well understood. The goal of the TANGO project is to take these familiar ideas about affective communication one radical step further by developing a framework to represent and model the essential interactive nature of social communication based on non- verbal communication with facial and bodily expression. TANGO will investigate interactions in real life contexts showing agents in daily situations such as navigation and affective communication. A central goal of the project is the development of a mathematical theory of emotional communicative behaviour. Theoretical developments and investigations of the neurofunctional basis of affective interactions will be combined with advanced methods from computer vision and computer graphics. Emotional interactions can be studied quantitatively in detail and can be transferred in technical systems that simulate believable emotional interactive behaviour. Based on the obtained experimental results and mathematical analysis, a new generation of technical devices establishing emotional communication between humans and machines will be developed. TANGO goes beyond the state of the art in theoretical scope, in methodological approaches and in innovative applications that are anticipated.