Personally Identifiable Information (PII) is defined as any data that permits the identification, by either direct or indirect means, of an individual to whom the information applies.

PII can directly identify a person (examples are name, address, phone number, social security number, any other ID number or code, and email address) or allow indirect identification in conjunction with other data elements. Such elements may include a combination of gender, race, birth date, geographic indicator, and other descriptors.

PII is often maintained in the form of unstructured data, i.e., in Microsoft Office documents, PDF files (example: W-2 records), or computer printouts. Files containing PII are best protected by encrypting them at the point of creation. Adequate protection covers the document lifecycle in its entirety and includes provisions for data transfers to other media, i.e., screen photos or print.