The best thing about this survey of the dominant style of documentary filmmaking over the past 40 years is its inclusiveness. Director Peter Wintonick and his colleagues from the National Film Board of Canada managed to track many of the big names, from D.A. Pennebaker, Richard Leacock, and Robert Drew to Barbara Kopple and the usually camera-shy Frederick Wiseman, for interviews. In some ways, that generous embrace is also the film's weakness; a movie twice this length would only begin to describe the contributions of these directors and their colleagues. The film rightly gives the NFB and filmmaker Jean Rouch much credit for fostering the movement and setting down its precepts. The production is intentionally informal. Wintonick and his small crew are often glimpsed getting in and out of a car or entering an interview subject's office. This contributes to the film's spirit of discovery and wonder, as if to say: "Look at us blokes making a movie about some of our heroes." It's a terrific way to introduce students to the subject or a nice nostalgia trip for those who grew up on these movies.