A White Paper Submitted to The National Academy of Science's Committee on Exoplanet Science Strategy: Observing Exoplanets with the James Webb Space Telescope

The James Webb Space Telescope (JWST) will revolutionize our understanding of exoplanets with transit spectroscopy of a wide range of mature planets close to their host stars ($<$2 AU) and with coronagraphic imaging and spectroscopy of young objects located further out ($>$10 AU). The census of exoplanets has revealed an enormous variety of planets orbiting stars of all ages and spectral types. With TESS adding to this census with its all-sky survey of the closest, brightest stars, the challenge of the coming decade will be to move from demography to physical characterization. This white paper discusses the wide variety of exoplanet opportunities enabled by JWST's sensitivity and stability, its high angular resolution, and its suite of powerful instruments. JWST observations will advance our understanding of the atmospheres of young to mature planets and will provide new insights into planet formation.