Life on Earth is a laboratory that has operated for billions of years, producing remarkably diverse, complex, and robust biological systems; however, significant challenges persist in understanding their operating principles and, therefore, their ability to be designed, manipulated, and produced. Mesoscale organization is integral in bridging scales between microscopic interactions and macroscopic material properties in soft materials. The Wilken Lab (www.samwilken.com) illuminates new physical mechanisms of mesoscale organization and engineers novel materials inspired by biological examples. We build phase-separated biomaterials from the bottom up and quantify them using precision experimental techniques. Cells operate by coordinating reactions to occur at the right time and in the right place, and one remarkable way that cells organize biomolecules to perform reactions is by utilizing the physics of binodal coexistence, called `liquid-liquid phase separation' (LLPS). We use programmable, multi-component model systems of biomolecular phase separation to investigate the transport of biomolecular information, stress, and light through soft, disordered materials, including auto-regulated networks, composite soft solids, and exotic photonic biomaterials. We strive to establish general organizational principles for phase-separated biomaterials, which will enable natural extensions to elucidate the physical mechanisms of biomolecular organization in living systems, design reaction pathways in synthetic cells and tissues, and contribute to understanding the prebiotic processes that led to the emergence of life on Earth.