NIST has published a draft guide for protecting PII

The NIST draft uses the work done by OMB (Office and Management and Budget) Memo from 2007: “information which can be used to distinguish or trace an individual’s identity”. NIST Provides a practical guide for organizations on how to handle PII, by distinguishing the varying levels of sensitivity of the PII as well as how it should be protected: http://csrc.nist.gov/publications/drafts/800-122/Draft-SP800-122.pdf