What is Food Sovereignty?

I used the expression 'food sovereignty' in my post on Growing Food Justice and Equity. What does it mean? It may be useful to give a little more context to this term which is still not widely known or understood.

In the following video Raj Patel, author of The Value of Nothing and Stuffed and Starved, explains what food sovereignty means, and why people around the world are fighting to have a say in their own food system. Food sovereignty is rooted in the need to address social and economic justice while protecting the environment. It requires that communities, provinces and nations all over the world have the ability to determine their own food and agriculture policies.