Abstract: Systems and methods for managing public key certificates and supporting the users thereof. The certificates are cryptographically encapsulated objects that bind the identities of their owners to public keys and provide digital signature mechanisms for other users to verify the binding and correctness of other attributes of the certificate. Certificates include double links that reflect their validation and position in a public certificates ledger, thereby preventing insertion or removal of certificates in the ledger. Certificate protocols of the system include requesting issuance of certificates, issuing and returning certificates to their requesting users, storing certificates in the certificates ledger, requesting and distributing certificates to transaction partners, verification of certificates by transaction partners, and revoking certificates by their owners. These protocols are performed as direct peer-to-peer transactions between the members of the system.