Mark Jeremy Causebrook was born in 1953. He joined the Planning Office, British Rail: London Midland Region, London Division in 1974, before becoming a Staff Entrant Management Trainee on British Rail: London Midland Region in Birmingham in 1976 to 1978. He then became Traffic Manager at Great Bridge steel terminal, above moving to Walsall to serve in the same capacity in 1979. In 1979 he was made the Assistant to the General Manager of British Rail: London Midland Region until 1981 when he became the Manager of Kensington Olympia Motorail Terminal until 1982. He was appointed the Head of Scheduled Services for British Rail: London Midland Region, London Division in 1982, before joining the Coal Management Unit, Nottingham in 1983. He worked as Personal Assistant to Jim Urquhart, British Railways Board Member, from 1984 to 1985 before joining Freightliner in 1985. He was TransPennine and West Yorkshire Manager for Regional Railways in York between 1986 and 1988, staying in York, he then served as Quality Manager for British Rail: Eastern Region until 1990. In 1990 he was made the Sector Director for Regional Railways Central, Central, and subsequently Central Trains in Birmingham until 1998. He served as Managing Director of Thameslink between 1998 and 2006. He became Director of First Class Partnerships in 2008, until he was appointed Chairman in 2012, before leaving that role in 2016.