Documentary - Telling - Frederick Wiseman - Hospital

Frederick's Hospital shows daily work in a New-York hospital. We are taken through medicine areas and we see doctors at their heavy duty, patients who are drunk, drugged, unhappy, Police officers etc. I like the work of camera, it looks that the characters did not know the camera was there :-). I would like to know how Frederick got permission to shoot some scenes? Had to get allowance from everyone or he just walked in Hospital and made shots?

The document has not solid structure as the films which I have analysed so far. It looks there is an introduction of different areas such as surgery, gynaecology, dissecting room followed Police work and a care of older people. The end is the priest speech and the last shot of the hospital outside.

I really like the atmosphere of the film. The black&white gives a mystery of life to the film. Whole document is emotionally charged and it is great "window" to see how a Hospital works even it is from 1970.