Abstract: A method for enhancing state patterns in object-oriented programming is provided. The method comprises combining state patterns with hierarchical finite state machines that have history mechanisms. Inheritance, polymorphism and reflection are used to create state objects and call methods associated with those objects, which execute event entry and event exit behavior. The present invention distinguishes between internal and external state transitions and allows users of the pattern to clearly define execution of entry and exit behavior by calculating class hierarchies in which parent classes define common behavior in child classes. The present invention more accurately represents the complexity of state machines reified as software objects.