As President of World Wide Fund for Nature (WWF) International, His Royal Highness. The Prince Phillip, Duke of Edinburgh pioneered an innovative scheme to bring together world religions in the name of conservation. This effort culminated with WWF's 25th Anniversary in Assissi, Italy, where top representatives of the world's major faiths gathered to issue declarations on the environment and to assess what their faiths had to say about nature. This gathering contributed to preserving the environment and promoted goodwill and understanding in an inter-faith context. This initiative helped reach untold millions worldwide with a conservation message through religious channels.

His Royal Highness has written a number of books on the environmental including Birds of Britannia (1962), Wildlife Crisis (1970) and The Environmental Revolution (a collection of his speeches from 1962 to 1977). His later speeches have been compiled in three other books entitled: A Question of Balance, Men, Machines and Sacred Cows, and Down to Earth.