A key manager provides a way to separate out the management of encryption keys and policies from application domains. The key manager may create cipher objects that may be used by the domains to perform encryption or decryption, without exposing the keys or encryption/decryption algorithms to the domains. A master key managed by the key manager may be used to encrypt and decrypt the domain keys that are stored under the control of the key manager. The key manager supports the rekeying of both the master key and the domain keys based on policy. Multiple versions of domain keys may be supported, allowing domains to access data encrypted with a previous version of a domain key after a rekeying.