Turner will take over Traffic Operations on 4 April 2004. Commenting on the appointment, Highways Agency Chief Executive Archie Robertson said, "I welcome the arrival of Derek Turner to the Highways Agency Board. He has a wealth of experience in devising and introducing technology and road improvement schemes. This is a pivotal role in ensuring the Agency meets its aims in tackling congestion, improving safety and protecting the environment. As Director of Traffic Operations, Mr Turner will be a member of the Highways Agency Board reporting to the chief executive."

Previously Turner was the Managing Director, of Transport for London Street Management. He was appointed to that post in May 2000, and was responsible for 550km of London's key roads – the Transport for London Road Network (TLRN). Part of his remit was to introduce measures which would improve streets for all road users, particularly pedestrians, cyclists, bus passengers and people with disabilities. This included creating the London Traffic Control Centre and the major redesign and pedestrianisation of Trafalgar Square. He was responsible for the design, introduction and operation of Central London's unique congestion charging scheme.

Turner was the Traffic Director for London, from 1991, until its incorporation into Transport for London in July 2000. In this role, he was instrumental in establishing, maintaining and monitoring 512km of Red Routes and devising Bus Lane Enforcement Cameras. Additionally he was asked by the government to create the London Bus Initiative which led to the transformation of London's bus services. Between 1980 and 1991 he held posts in various local authorities in London, including the GLC, Wandsworth and Haringey, where he was appointed Borough Engineer and Surveyor in 1989.

A graduate in Civil and Structural Engineering from Sheffield University in 1974, he is a Chartered Civil Engineer. He frequently gives evidence to the Transport Select Committee of the House of Commons and lectures internationally. He has served on numerous professional bodies and committees and was recently invited to join the University College London to be an Advisory Panel Member for the Civil and Environmental Engineering profession and appointed a Visiting Professor at the Centre for Transport Studies. He was Chairman of the Institution of Civil Engineers Transport Board from 1999. In June 2003 he was awarded the CBE for his services to transport in London.