Ian Liddell

For the British recipient of the Victoria Cross, see Ian Oswald Liddell.

Ian Liddell CBE FREng FIStructE Hon FRIBA
Born	William Ian Liddell 1938 (age 85–86)
Nationality	British
Education	Cambridge University, UK and Imperial College, London, UK
Occupation	Engineer
Engineering career
Discipline	Structural engineer, Engineering design
Institutions	Fellow of the Institution of Structural Engineers, Member of the Institution of Civil Engineers, Fellow of the Royal Academy of Engineering, Honorary Fellow of the Royal Institution of British Architects
Practice name	Buro Happold
Projects	Sydney Opera House Timber Gridshell, Mannheim, Germany Millennium Dome, London The Globe Theatre, London The State Mosque, Sarawak
Awards	CBE, IStructE Gold Medal, Royal Academy of Engineering, MacRobert Award, Award of Merit in Structural Engineering

William Ian Liddell (born 1938) is a structural engineer and the designer of London's Millennium Dome. He was one of the founding partners of Buro Happold and is a Royal Academy Visiting Professor of Engineering Design at Cambridge University School of Engineering. He is now a consultant for Buro Happold.

He studied mechanical sciences at St John's College, Cambridge followed by a diploma in concrete structures at Imperial College, London.

He was project engineer on the Sydney Opera House, playing a significant role in the formfinding of the iconic roofs. He received the IStructE Gold Medal in 1999.

For his work as Chief Design Engineer on London's Millennium Dome project, he was appointed Commander of the Most Excellent Order of the British Empire (CBE) in the 1999 New Year Honours.

He is a trustee of the Arkwright Scholarships Trust and the Smallpeice Trust.