The TC-204 Symposia have been traditionally high-level events, where specialists from around the world join to present and discuss their contributions and experiences in underground construction in soft ground. This time, it will be held in Brazil, a large country with enormous needs and potential for underground construction. The 9th IS will take place in São Paulo, together with the 4th Brazilian Tunneling Congress and the Latin American Tunneling Seminar, two events that have been usually held in São Paulo, and traditionally joined over 600 local and international specialists.