Paper, broadly defined as thin, porous sheets, is currently being used to create novel devices for diagnostics, microfluidics, and electronics that ideally combine low cost and high performance. A “device,” in this context, can be defined as an object that serves to provide information or function to a user in response to input. This issue will highlight some of these novel devices and provide examples of potential applications. We begin with an overview of paper’s unique properties and how these properties lead to a potential for changing the integrated microfluidic and flexible electronics landscape. We then discuss methods for patterning paper as well as specific fluidic operations that are possible on paper. Finally, we conclude with an overview of electronic devices on paper and a brief outlook on the future of this emerging field.