IISS

The International Institute for Strategic Studies (IISS) is an Independent strategic-studies institute founded in London in 1958. It has offices in London, Washington, Manama, Singapore and Berlin. Its best-known work is The Military Balance, an annual reference on armed forces, defence spending and equipment inventories. It also publishes Strategic Survey, the Adelphi Papers and the peer-reviewed journal Survival, and hosts the Shangri-La Dialogue in Singapore and the Manama Dialogue in Bahrain.

Its value lies in comparative defence data and analysis published outside government classification. That gives policymakers, journalists and researchers a common public baseline, and its analysts have been cited on questions from Hormuz transit fees to Britain's planned uncrewed warships. Through the 2026 Iran war its assessments ran from a March warning that the conflict risked becoming a battle of endurance, to an April Survival paper judging that all three combatants would likely claim victory while ending strategically worse off, to a July view that no military option could reopen Hormuz.

That standing also makes its name useful to others. Microsoft reported on 29 September 2026 that Star Blizzard, a group it ties to Russia's FSB, sent phishing lures styled as event invitations from bodies including the IISS.