A replicated database system is a distributed database system in which some data objects are stored redundantly at multiple sites to improve the reliability of the system. Without proper control mechanisms, the consistency of a replicated database system might be violated. A scheme to increase the reliability as well as the degree of concurrency is described. It allows transactions to operate on a data object if more than one token copies are available. The scheme also exploits the fact that, for recovery reasons, there are two values for one data object. Proof that the proposed scheme guarantees consistency is provided. Some of variations of the scheme are discussed.