Certificate Transparency is a security framework designed to make the issuance of digital certificates more open and accountable. It works by requiring certificate authorities (CAs) to publicly log every certificate they issue in append-only, tamper-evident logs. This allows anyone to monitor and audit these logs for suspicious or unauthorized certificates, helping to quickly detect fraud or mistakes. By increasing visibility into the certificate ecosystem, Certificate Transparency helps protect users from attacks that exploit rogue or misissued certificates.