In the realm of application integration we see one hype after the other. The message broker was succeeded by the service bus and service oriented architecture, today it is microservices and API's. The advocates of these technologies promise a great deal, but in reality most implementations fail to deliver. Are these technologies flawed? No, it is not the technology that creates a flawed implementation, it is the people using the technology who design flawed implementations. Vendors of integration tooling and programmers have published an extraordinary amount of information on the technical aspects of application integration. Unfortunately, there is remarkably little guidance on how to design successful application integration solutions. This is largely caused by the outdated view that application integration is nothing more than sharing data between applications. The premise of this eBook is that application integration is about how to support your business processes across a network of well-integrated heterogeneous applications. By exploring integration architecture and its relation with enterprise architecture this eBook provides guidance on how to design successful application integration solutions regardless of underlying technology.