William Daniels' work revolves around social issues and humanitarian concerns mostly focusing on isolated or weakened communities. His past projects have focused on malaria, AIDS and tuberculosis, as well as the aftermaths of the tsunami in Asia and the earthquake in Haiti. He has also covered conflict in Libya, Kyrgyzstan and Central African Republic.
His long-term work on malaria was exhibited on the Pont des Arts bridge in Paris, in London, at the European parliament in Brussels in partnership with the Global Fund, and published in the book Mauvais Air. He also published Faded Tulips, a long term vision of the post-Soviet democracy in Kyrgyzstan. His images appear regularly in the French and international press: National Geographic, Time, Newsweek, The New York Times, Le Monde, and Polka.
He is represented by the London-based agency Panos Pictures and by the agency Myop in France.