Multilateral collaboration is an important component of the Chinese Academy of Engineering’s international collaboration. The CAE maintains memberships in a number of international organizations including the International Council of Academies of Engineering and Technologies Sciences (CAETS), the InterAcademy Partnership (IAP), etc., and is a founding member of the InterAcademy Medical Panel (IAMP, now IAP for Health). As the host of two Category II Centres under the auspices of UNESCO, the CAE is also engaged in collaboration with UNESCO and other related UN bodies. The two UNESCO Category II Centres hosted by CAE are: The International Knowledge Centre for Engineering Sciences and Technology (IKCEST, http://www.ikcest.org/ , since 2014) and the International Centre for Engineering Education (ICEE, in collaboration with Tsinghua University, since 2016). A number of activities and projects have also been carried out under other multilateral mechanisms such as the East-Asia Roundtable Meeting (EA-RTM, between CAE, the Engineering Academy of Japan and the National Academy of Engineering of Korea), and the Global Grand Challenges Summit (GGCS, between CAE, the UK Royal academy of Engineering and the US National Academy of Engineering). Each year, CAE hosts about 20-30 international forums in the fields of Engineering and Technological Sciences.