With the development of the Internet of Services, composing loosely-coupled, and autonomous services dynamically has become one of the new challenges for large scale computing. While service composition systems are now a key feature of service oriented architectures, the coordination and execution of service compositions are still typically conducted through heavyweight centralized architectures, leading to problems related to scalability and reliability. In this book, we present a workflow management system able to solve a wide variety of workflow patterns in both a centralized and a decentralized way following the chemical model. Within this model, data and services are seen as molecules floating and interacting freely in a chemical solution. The decentralized workflow execution coordination is achieved through a set of reactions between those molecules. While its high expressiveness and adequacy for this context is being established, the chemical model severely suffers from a lack of proof of concepts. To tackle this problem, a prototype has been developed. Its implementation and evaluation in actual settings are discussed,establishing the viability of the concept.