An arrangement sanitizes a digital data storage unit, such as a disk data storage unit, by encrypting the information that is stored thereon. When the previously-stored information is retrieved from the digital data storage system storage unit, the information is decrypted prior to being provided to the device that requested retrieval of the data. If the digital data storage unit is to be sanitized, the key or keys that used to at least decrypt the data stored on the digital data storage unit are discarded or made unavailable for use in decrypting the encrypted digital data, thereby making the unencrypted data unavailable. Any of a number of types of encryption/decryption methodologies can be used, including a symmetric key methodology, an asymmetric key methodology such as a public key/private key methodology, or any of a number of other encryption/decryption methodologies.