The next frontier in exoplanet research is discovering, characterizing and understanding small exoplanets (sizes below 4 Earth radii), allowing a detailed comprehension of this region of parameter space where planets like our own Earth reside. Advancements in this area of research will lead to an understanding of the diversity and composition of these planets, estimates of the true occurrence rate of rocky worlds with the potential of accommodating liquid water on their surfaces, and help advance planet formation theories struggling to understand how these planets are formed.
Thousands of these small worlds have recently been discovered, yet we know very little about them except for their sizes and orbital periods. In fact, the majority of these small planets have sizes that range between that of the Earth and Neptune and thus have no Solar System analogues. In this talk, I will review the latest advances in our attempts to characterize these small planets and the stars they orbit, including local efforts at CfA to precisely measure their masses, allowing us to determine the bulk compositions of the planets that transit. I will set the stage for the near future, where a plethora of upcoming missions and instruments promise to revolutionize our understanding of the small exoplanets.