George R R Martin, he ranks fourth on The Hollywood Reporter's annual list of "Power Authors", which ranks the writers with the most influence on television and film.
J K Rowling took the top spot, perhaps unsurprisingly given the eagerly awaited film Fantastic Beasts and Where to Find Them, which will be released next month.
Stephen King, who has seven movies and two television shows in production, ranks second, followed by James Patterson, whose Middle School series has been adapted for a film that will be released in the United States this week.
Perhaps more interestingly, a new generation of writers is making waves with film adaptations of their work, including Paula Hawkins (No 19) for The Girl on the Train, Lauren Oliver (No 23) for Before I Fall and Patrick Ness (No 24) for A Monster Calls.
