In recent years, advances in computational and experimental capabilities have enabled us to push the experimental frontier to unprecedented conditions and to observe and model more complex planetary systems. While exoplanet observations continue to detect and characterize smaller bodies from super-earth to sub-earth in size, experimental studies of planetary building blocks have allowed us to ask questions about ever larger planets. We call on experimenters, calculators, and modelers to contribute their studies of planetary interiors, their component minerals, and mineral assemblages. We seek contributions on the effect of composition and volatiles on phase diagrams, equation of states, and transport properties of minerals at extreme conditions. We also invite those who use these properties to study exoplanet formation and subsequent evolution.