I had to leave off quite a few directors that will probably make it on to my list, but right now I haven't seen enough of their films to justify it. My ranking is loosely based on the number of movies from them I love, their consistency, and in some cases, influence as a filmmaker.
20. Edgar Wright
19. Alfonso Cuaron
18. Ridley Scott
17. Takeshi Kitano
16. Danny Boyle
15. Guillermo Del Toro
14. Christopher Nolan
13. Orson Welles
12. Steven Speilberg
11. The Coen Brothers
10. David Lean
09. Quentin Tarantino
08. Charles Chaplin
07. David Fincher
06. Stanley Kubrick
05. Paul Thomas Anderson
04. Alfred Hitchcock
03. Brad Bird
02. Akira Kurosawa
01. Hayao Miyazaki