Between 2001 and 2003 the London Health Commission undertook health impact assessments (HIAs) on a series of strategies developed by the Greater London Authority and the Mayor of London. The HIAs were rapid, each involving a literature review and a participant workshop. In all cases the reports made a series of recommendations that were given to the Mayor. The HIAs led to changes and ensured that health and health inequalities were given due consideration as part of the strategy development process.