A data processing device and method adapted for key management are provided. A first encryption key associated with a first password is generated, and at least a further encryption key associated with a further password is generated. Generation of the encryption key may use the associated password, a key seed, and a current key. The first encryption key and further encryption key or keys are stored in memory, and are used to encrypt and decrypt separate sets of data. Different keys and potentially different levels of encryption are thus used to protect different sets of data at the device.