Usage-centered design is a systematic, model-driven approach to visual and interaction design with an established record of effectiveness in a wide variety of settings and areas of application. The tutorial introduces the models and methods of usage-centered design and explores the integration of usage-centered approaches into software engineering practice. Agile approaches to modeling will be emphasized, with the focus on use cases, which are central to usage-centered design and serve as a common thread throughout an integrated usage-centered software engineering process.