Festing did voluntary work for
Greenpeace from 1992 to 1994, before joining
Friends of the Earth in 1994, where he was employed as their transport and wildlife campaigner until 1998. He worked as a campaign leader for
Help the Aged from 1998–1999, then became Director of Public Dialogue for the Association of Medical Research Charities, an umbrella group representing 100 medical-research charities, a post he held from 2000 until 2004, when he joined the Research Defence Society (RDS). He was chief executive of
Understanding Animal Research (formerly RDS) from 2004 until June 2011. After this he was Chief Executive af a number of charities and professional bodies, including the
Microbiology Society, Chartered Institution for Water and Environmental Management (
CIWEM), and the British Healthcare Trades Association. ==Public profile==