Mr Sims began his policing career in 1980 with the Metropolitan Police force, rising to the rank of chief inspector.
He moved to Staffordshire Police in 1994 on promotion to superintendent. He worked in the professional standards unit, helped establish the performance development team, worked in CID at headquarters and spent a short time as divisional commander at Wombourne before taking up the role of divisional commander at Hanley.
He left Staffordshire in March 1999 to take up the role of Assistant Chief Constable for West Midlands Police. Mr Sims was later appointed Deputy Chief Constable – a post he held for three years. During his time with West Midlands Police, Mr Sims was seconded to Nottinghamshire Police to act as a strategic advisor.
Before taking up his previous role as Chief Constable of Staffordshire in September 2007, Mr Sims was the Deputy Chief Executive and Director of Policing Policy and Practice at the National Policing Improvement Agency (NPIA) based in London. He was responsible for research and evaluation, doctrine development and implementation and portfolio management.
A graduate of St Peter’s College, Oxford, Mr Sims also achieved an MBA from Warwick University.
Mr Sims took up new responsibilities as Chief Constable of West Midlands Police on 1 June 2009.
He was awarded the Queen's Policing Medal (QPM) for distinguished service in the Queen's Birthday Honours List in 2010.