The invention provides a method of and system for secure application of seals. An optical image of a seal is recorded by a computer and encrypted using a key for encryption generated in response to template biometric data from authorized persons. When a person seeks to use the seal, for example to apply the seal to a document, test biometric data is input from that person and used to generate a key for decryption. If the test biometric data matches the template biometric data, the key for decryption will be useful for decrypting the encrypted seal, and the person seeking access to the seal. The test biometric data represents a handwritten signature given contemporaneously by the person seeking access, and is verified against a set of template signatures earlier given by at least one authorized person. Specific signature features are determined in response to the template signatures and used for generating one or more keys for encrypting the seal. Similarly, specific signature features are determined in response to the test signature and used for generating keys for decrypting the seal. Features are embedded in the optical image of the seal, or in the printed seal in the event that the document is physically printed, which demonstrate to a person examining the document that the seal is genuine. These features include microembedding of biometric data or specific features determined in response thereto.