Security policies are actually very flexible documents. Your security policy can be one large document that incorporates an e-mail policy, an Internet Usage policy, an Acceptable Use policy, etc. You can also break each of these topics out into its own policy. I prefer to break policies out into individual sections and have one summary document. I feel end users approach the concept of security policies much more positively that way. Instead of handing them a 100 page document to read, they get a bunch of smaller documents.
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