(Editor's note: Today, London celebrates 40 years of Gay Pride and hosts World Pride, a global jamboree of LGBT campaigners from all over the world. The theme of today’s Pride parade is: “Decriminalize homosexuality worldwide - Global equality for LGBT people.” Peter Tatchell, director of the human rights advocacy group the Peter Tatchell Foundation, discusses the importance of global equality. He helped organize Britain's first Gay Pride Parade, held in London 40 years ago in July 1972. He is a Patron of Pride London.)