While watching Elia Kazan's 1951 film, A Streetcar Named Desire, based on Tennessee Williams' 1947 play, I felt that the actors and actresses were so comfortable in their settings. They all played their parts as if they knew the people really well that they were playing. I know that is what actors and actresses are supposed to do regularly, but it was put into perspective after watching the autobiography of Elia Kazan, A Director's Journey.
Kazan is different from a lot of other directors in that he let the players bring their respective character out for themselves. Not to say that he did not try to help them pull out the true colors of a character, but he allowed the actors and actresses to perform mainly on their own. Kazan just figured they were right for the part and had faith that each actor/actress would accomplish the character in his/her own time. I believe that made his movies and life story stand out from other directors.
The players in the movie A Streetcar Named Desire, for example Marlon Brando as Stanley, Kim Hunter as Stella, Vivien Leigh as Blanche, and Karl Malden as Mitch, really did an exceptional job of pulling their characters out. It is safe to say, in my opinion, that Kazan did a great job of casting and letting the actors find their own characters. If Kazan had tried to have more power over the development of the characters the movie might not have been the sensation that it was.
I have learned that directors really are the glue behind a movie. They pull it together, hold it together, and add in the missing pieces to make a movie everything that it is. There are so many more aspects such as scenery, costumes, music, and cinematography; but I believe the director plays a big part. Kazan is brilliant to have cast based on what the actors and actresses could bring to plate instead of what he could make them bring.