Method, system and program product for managing processing groups of a distributed computing environment

The management and use of replicated distributed transactions is facilitated. A distributed synchronous transaction system protocol is provided to manage the replication of distributed transactions for client application instances. The distributed synchronous transaction system allows transactions to be replicated without having the client application instances be aware of other instances to receive the transaction. Further, if a failure occurs during processing of a distributed replicated transaction, the distributed synchronous transaction system manages the recovery of the failure. In such a system, processing groups are managed by comparing at least a portion of a state of a prospective member of a processing group with at least a portion of a group state of the processing group; by updating said at least a portion of the state of said prospective member, should said comparing indicate a difference; and by joining said prospective member to said processing group.