I want to create an excel file for every cost centre in my organisation
Each file will have a unique password that is known by the cost centre manager (and myself obviously)

My question is - can I have an additional password that only I know or a few people know that can open any of them?

So each file would have 2 passwords, where one is a 'master' password that opens all the files.

I have Excel 2007.

Many thanks
David