Making a Documentry?

Question:

Making a Documentry?

I am making a documentry (short film) about the past 2 years and current year until July 2007,of a part of my life(I dont wish to disclose what it is though)
Any suggestions how to keep it meaty and how I should go about filming myself in public and things AND do I need peoples written permission before I film them or should it be fine just to have verbal permission.

Best Answer - Chosen by Asker:

YOU MUST!!! have written permission I found that out the hard way when i went back to my old high school and did a documentry