Optimistic replication accepts changes to replicated data sets without immediate coordination, with the assumption that conflicts can later be resolved by a separate protocol. This protocol will subsequently reconcile changes between replicas, and detect and resolve any conflicts. In this paper we present a log-based reconciliation architecture that is designed to record and reconcile changes to data efficiently in terms of communication and storage overhead. Redundancy is eliminated through the use of a log-based storage mechanism. A general data model accommodates a large variety of data types. Because of its storage efficiency, the architecture is especially suited to small data such as database records.