Raindrops similar or greater in size to the largest ever observed, with maximum dimensions of at least 8.8 mm and possibly 1 cm, have been measured in rainshafts beneath cumulus congestus clouds spawned by a biomass fire in Brazil and in very clean conditions in the Marshall Islands. It is proposed that the super-large raindrops were produced by the rapid growth of drops colliding with each other within narrow regions of cloud where liquid water contents were unusually high. In Brazil, the initial growth of super-large raindrops might have been initiated by condensation onto giant smoke particles.