People process information at different levels of abstraction (e.g., talking about a topic in general terms and then going into the details). They move from one level to another but focus on a particular level at any specific moment. We see this behavior in the most common of tasks, such as solving problems, communicating and designing. This paper explores the implications of levels of abstraction on designing interactive systems. It demonstrates the idea by showing the feasibility and desirability of building a simple e-mail system based on the idea of levels of abstraction and testing its usability.We believe the implications of levels of abstraction on design are profound as regards the design of interactive systems that support dynamic behavior. Having shown the feasibility of some basic design implications, we call for empirical studies to test their usability and explore more advanced design implications.