The currently observed architectures of extrasolar planetary systems trace the processes of planetary formation and evolution. Until recently, Jovian-size planets provided nearly all of the observational constraints. From Doppler studies, we detect a steeply rising planet mass distribution down to at least 3 Earth-masses for planets orbiting inside of 0.25 AU. The planet size distribution from Kepler also shows a steep rise with decreasing size, but with a plateau in the occurrence rate for 1-2.8 times Earth size. Analyses of the Kepler data support the bottom-up picture of planet formation by core accretion.
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