Radio Science techniques have advanced solar system exploration over the past five decades via studies of planetary and solar phenomena, and fundamental physics. This session encompasses radio science investigations using radio and optical techniques to study planetary and small body interiors (including ocean worlds), the structure and dynamics of planetary atmospheres, characterizing the scattering, electrical, and other properties of planetary surfaces, ionosphere/solar plasma characterizations accessible via multifrequency links, and research in solar system dynamics and fundamental physics. Technologies relevant to this session include the design of small spacecraft networks and constellations including smallsat pairs such as GRAIL, and mission concepts comprising multiple entry probes, advances in space clock technologies, novel communications architectures including optical links, advances in radio and laser technologies, flight and ground instrumentation, and new instrumentation and techniques for entry probe radio science.