After nearly 30 years service with the TUC, Sir Bill became Chair of the Health and Safety Commission in 1999.He served as a founder member of the Low Pay Commission from 1997 to 2000. In 2007, he led a review into the regulation of animal pathogens for Defra. He was an independent member of the Joint Negotiating Committee for Higher Education Staff review of higher education finance and pay data from October 2007 to December 2008. He became Chair of the Legal Services Commission in 2008 (a Ministerial Public Appointment with remuneration of £54,000 pa). He is also a Magistrate and has recently been appointed Chair of the National Examination Board for Occupational Safety and Health (an educational charity).

Sir Bill Callaghan has played a leading role in ensuring and managing health and safety in the workplace. He was instrumental in driving forward the 'Revitalising Health and Safety' initiative, key dimensions of which included director leadership of health and safety, workforce involvement, performance improvement targets and the creation of HSE priority topics. He also championed the development and implementation of HSC's strategy to 2010 and beyond, which has led to a strengthening of HSE's partnership with local authorities and a reinvigoration of HSE's occupational health agenda, integrating this with the Government's plans to improve health, work and well-being.

Prior to taking up appointment as HSC Chair, Sir Bill Callaghan was the Chief Economist and Head of the Economic and Social Affairs Department at the TUC. He served on the Low Pay Commission from 1997 - 2000 and played a key role in the introduction of the National Minimum Wage in April 1999.