The Integration Rules (IRules) project is investigating the use of active rules for supporting event-driven activity in applications involving distributed component integration. Integration rules respond to events that are raised during the execution of distributed transactions to evaluate conditions and trigger actions over distributed components that are implemented using the Enterprise Java Beans (EJB) component model. This paper presents the distributed architecture for the IRules environment and defines the execution and transaction model for the use of integration rules. The execution model includes traditional active rule coupling modes for immediate, deferred, and decoupled rule execution and also defines an asynchronous mode for concurrent rule and transaction execution. The flexible transaction model is used to allow integration rules, application transactions, and methods on EJB components to be executed as subtransactions within global distributed transactions. An execution scenario for the integration of EJB components is presented to illustrate the nested execution of rules and transactions for distributed component integration.