 Firrell has used digital billboards, cinema screens, newsprint, the internet, portraiture and video interviews of culturally significant figures like Howard Jacobson, April Ashley, Johnson Beharry VC, and A C Grayling, and large-scale digital projection onto the Guards Chapel, spiritual home of the Household Division of the British Army, the National Gallery in London, the Houses of Parliament, the Royal Opera House, Covent Garden, Tate Britain, and St Paul's Cathedral.Firrell has worked with complex and influential organisations, including the Church of England (Public Artist in Residence, St Paul's Cathedral, 2008 and again in 2016) and the British Army (Artist in Residence, Household Division, 2009).These organisations have engaged with audacious, self-questioning project content, including "I don't think this is what God intended" (West Front, St Paul's Cathedral, 2008) and "War is always a failure" (North elevation, Guards Chapel, 2009).