Several existing research protocols have already studied long running transactions within a formal context and many of them seemed to use concepts which are not suitable. However, there still exists a great challenge to perform transactions in the loosely coupled environment. In this paper we present formal model for compositional protocol with the asynchronous .."calculus with compensation and exception handling. We study the practice of ..RBTcalculus, by discussing few paradigmatic examples, its theory, by defining semantics and providing a correct encoding of ..RBT-calculus into asynchronous .." calculus. ..RBT-calculus is a business process modeling protocol and a distinctive feature of the language is its support for compensation. Compensation is an action taken to recover from error or cope with a change of plan, especially when rollback of a process is not possible. We also propose a process-oriented transactional business coordination model with hierarchical structure. It allows dependencies across hierarchies and supports various transactional behaviors of different services. Based on this model, a novel failure recovery algorithm is presented. It can ensure semantic atomicity for long running Web services composition. Analysis shows it can effectively reduce compensation sphere and thus decrease costs.