The activities developed by a company (business processes) have to change frequently to adapt to the environment. The implementation of business processes should support these changes without any recoding. In this work, we provide with an approach for modelling and executing agile and adaptable business processes. Our approach is based on UML 2 separating choreography (stable interaction patterns) and orchestration (implementation of the evolving business process, also called workflows), allowing the transformation and execution of the models by means of a flexible SOA-based dynamic platform based on reference Petri nets.