This paper proposes a generic interactive system architecture describing in a structured way, both hardware and software components of an interactive system. It makes explicit all the components that play a role in the information processing from input devices to the interactive application and back to the output devices. Along with the generic interactive system architecture the paper proposes a process for selecting and connecting those components in order to tune the generic interactive system architecture for a specific interactive application. This select, connect and tune-on-demand approach helps handle complexity of interactive applications featuring innovative interaction techniques by splitting the interactive software into dedicated functional components. It also supports design flexibility by making explicit the components impacted when the interaction design evolves. This interactive system architecture and its related process have been applied to the development of several real-life interactive systems and we illustrate their application on an interactive application offering multi-mice, multi-touch and leap motion interactions in the context of interactive cockpits of large civil aircrafts.