The laws of equilibrium statistical mechanics impose severe constraints on the properties of conventional materials assembled from inanimate building blocks. Consequently, such materials cannot exhibit spontaneous motion or perform macroscopic work. Inspired by biological phenomena such as ciliary beating, Drosophila cytoplasmic streaming and actin treadmilling, this IRG will develop an entirely new category of materials assembled from animate, energy-consuming building blocks. Released from the constraints of equilibrium, such materials will acquire new functionalities. For example, in contrast to conventional gels, which remain quiescent unless driven by external forces, the spontaneous internal flows of active gels exert macroscopic force on the boundaries of a rheometer. Such force-producing active fluids are just one example of highly-sought biomimetic functionalities that are found in internally driven active materials. Fully functional biological structures are fragile and difficult to control and are thus poorly suited for materials science applications. To overcome this limitation, we will develop tunable and robust biomimetic systems from a few well-characterized building blocks. These systems will serve as an ideal platform for developing novel material applications, testing fundamental models of far-from-equilibrium active matter, and potentially shedding light on self-organization in living cells. Ultimately, our work will bridge the chasm between the remarkable properties of animate biological organelles or cells and traditional materials science, which has focused on building inanimate structures.