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Sir Jon Day

Since joining the Ministry of Defence in 1979, Jon has held posts responsible for policy, strategy, intelligence and operations, transformational change and the management of military resources in MOD, the Foreign and Commonwealth Office, NATO and the Cabinet Office.

His early career included operation policy during the Falklands War, Ministerial private office and strategic policy planning.  In NATO, first with the FCO and then the International Staff, Jon was intimately involved in developing the strategy for the Alliance’s post-Cold War transformation, including Partnership for Peace and Balkans crisis management.  Subsequently, as Deputy Command Secretary LAND he managed the Army’s £3bn operating budget.

Returning to the MOD, Jon led both the Royal Navy’s change programme as Command Secretary FLEET and the Head Office Streamlining Project.  He was successively Director Operational Policy, dealing with Iraq, Afghanistan and counter terrorism, and MOD’s Director general Security policy during the 2010 Strategic Defence and Security Review, playing the lead role in nuclear, NATO/EU and transatlantic security policy.

In 2011, he was appointed MOD’s Second Permanent Under Secretary – the Department’s joint chief operating officer – before becoming Chairman of the Joint Intelligence Committee and the Prime Minister’s primary adviser on intelligence in 2012.