Two airlines are in the redaction news recently as one begins redacting frequent flyer numbers and another has a pricing plan unintentionally exposed.

Researchers at the University of Illinois have uncovered new ways of finding vulnerabilities in redaction processes, drawing extra attention to how difficult redaction is to get right.

Misapplied redactions always seem to show up in the news, but why? We’ve narrowed it down to frequency, impact, and knowledge.

We know that documents containing personal information should be redacted, but what information needs to be redacted and what’s the best way to do it?