“The world faces great challenges and society increasingly looks towards science to address them. This places demands on all fields of science in all parts of the world. It compels a global response, involving strengthened collaboration within the international scientific community and between it and the world of policy and business, civil society, and the public at large”, the Presidents of the ICSU and the International Social Science Council (ISSC) stated in a joint letter. The ICSU Executive Board and the ISSC Executive Committee therefore decided to consult their members on the possibility of merging the two Councils.
Thus, an extraordinary ICSU General Assembly was held in Oslo, Norway, on 24 October 2016 jointly with the ISSC. IUSS was represented by Takashi Kosaki. The decision of the joint Assembly was to approve the merger in principle and to allow the two Councils to develop a strategic and transition plans for setting up a new international science council.
Despite a reportedly significant number of ICSU unions being against the merger, 76% of ICSU Members and 87% of ISSC Members voted in favour of a future merger of the two organizations. The final decision on the merger will be taken by the membership of ICSU and ISSC at the ordinary General Assembly of ICSU in October 2017.
More details can be found here