Small stars and small planets are ubiquitous in the Galaxy. Planets smaller than ~2.5x the Earth's size occur more frequently than any other type of planet; stars smaller than ~0.4x the Sun's mass are the most common type of star. These systems offer a unique laboratory to study the atmospheric makeup of previously unknown types of planets --- nonetheless we know much less about the formation, evolution, interior composition, atmospheric makeup, and population trends of M dwarf planetary systems than we do for planets orbiting Sunlike stars. I will review our work to shed further light on the matter, including my team's large HST survey of transiting super-Earth atmospheres and a search for new, small planets transiting M dwarfs using NASA's new "K2" mission. These projects provide the foundation necessary to enable many future exoplanet observations with ground-based telescopes and NASA's upcoming space missions.