The IOC Committee on International Oceanographic Data and Information Exchange held its Twenty-first Session (IODE-XXI) at the Palais des Congrès, Liège, Belgium between 23 and 26 March 2011. The Session was attended by 74 participants from 36 IOC Member States and seven organizations. The Session’s outcomes included: (i) the further steps towards the adoption of OBIS by IODE, including the recommended establishment of an IOC Project Office for IODE/OBIS; (ii) the continuation of the IOC Project Office for IODE in Ostend, Belgium; (iii) a Statement on the IODE role in the ICSU World Data System; (iv) the planned further expansion of OceanTeacher to include a wider range of IOC disciplines as well as the recommended development of a five-year training plan; (v) the planned revision of the IOC Strategic Plan for Oceanographic Data and Information Exchange (2012–2015). The Committee elected Ms Sissy Iona (Greece) and Mr Ariel Troisi (Argentina) as IODE Co-Chairs.