Abstract: Exoplanets outnumber stars in the Milky Way, and small worlds with radii less than 4x Earth’s radius are the most common. Despite being all around us, terrestrial exoplanets are the most difficult planetary type to study because they produce small signals with techniques we use to study exoplanets and their atmospheres, such as transit spectroscopy. To maximize detection and characterization signals we take advantage of “the M dwarf opportunity,” whereby the relative radii and masses between small planets and small stars boosts the transit and radial velocity signals we are looking for. Today, JWST’s infrared capabilities, pointing stability, and 25 square-meter collecting area are giving us unprecedented access to rocky worlds orbiting our closest M dwarf neighbors. However M dwarf host stars are more variable than expected, and can imprint stellar molecular features on planetary transit spectra. In this talk I will present the state of the field of terrestrial exoplanet science in the JWST era, including the latest results, toughest challenges, and brightest prospects for discovery.