S Rajaratnam School of International Studies (abbreviated RSIS) at Nanyang Technological University (NTU) was established on 1 January 2007. The school came about as an expansion of the Institute of Defence and Strategic Studies (IDSS), which was established in 1996.

The school is named after the late Mr. S. Rajaratnam who held various Cabinet appointments until his retirement. He was also one of Singapore’s founding fathers and well respected as a visionary diplomat and strategic thinker.

Constituents of RSIS include

• the Institute of Defence and Strategic Studies
• the International Centre for Political Violence and Terrorism Research (ICPVTR),
• the Centre of Excellence for National Security (CENS),
• the Asian Programme for Negotiation and Conflict Management (APNCM).

RSIS claims to exist to "develop a community of scholars and policy analysts at the forefront of Asia-Pacific security studies and international affairs." The School's motto is to “Ponder the Improbable”. Its research, teaching and networking objectives are aimed at assisting policy makers to develop comprehensive approaches to strategic thinking in areas related to Singapore’s interests.