The 42-year-old actress - who has sons Sacha, three, and Kai, two, with long-term partner Liev Schreiber - plays real-life former undercover CIA agent Valerie Plame in new movie `Fair Game` and admits she would struggle to live her life if she had to be as secretive as her character.
She said: "I believe in honesty all the way. Liev knows everything about me. I don`t think I could have done that - walk out the door and not say I was going to a foreign country as Valerie did in her job. Maybe she didn`t see it as lying so much as withholding the truth."
Naomi also admitted her children still don`t really understand her work but get excited when they see their parents on television.
She told Stylist magazine: "They don`t really understand it yet. There have been times when they`ll see a flash of us on TV and they`ll go, `Oh mummy!` then they come to the set and think our work is in a trailer. That`s our office.
"I did a film called `The Impossible` with Ewan McGregor, a story based on the tsunami and that one was quite difficult for them because they saw me in quite a bad condition. I just had to explain the `owies` - bruises - were just pretend."