This paper reports on two experiences of Social Dreaming Matrix in the context of the IAGP Congress in Sapporo. In particular, the pre-conference session, which illustrated and worked on the method and its implementation, and the subsequent session, which combined Morenian sociodrama with SDM as a methodology constituting the basic matrix of sociodrama. A double action method between imagination and dramatisation, starting from the social vision of dreams as the collective unconscious. The work on dreams therefore determines a double founding myth of the mental field of the Collective in action. The SDM also had a place within a more academic context in the symposium on the theme and history and theory of the method.