Think about the photo before and after, never during. The secret is to take your time. You mustn’t go too fast. The subject must forget about you. Then, however, you must be very quick. Henri Cartier-Bresson

Originally posted on Photofocus (old site):
Think about the photo before and after, never during. The secret is to take your time. You mustn’t go too fast. The subject must forget about you. Then, however, you must be very quick. – Henri Cartier-Bresson