Data on the growth of the large marine snail Strombus gigas was obtained from specimens collected as veligers in the plankton and reared through metamorphosis, from larger individuals (5.5 cm) reared in a mariculture system, and from field tagrecapture experiments. Using the von Bertalanffy growth equation, I estimate that 1, 2, and 3 year-old juvenile snails are 10.8, 17, and 20.5 cm in maximum shell length, respectively. The snails reach the flaring-lip stage after 3 years and have a mean longevity of another 3 years. Approximately 12% of the total weight of a juvenile snail is marketable meat. Measurements of meat weight, shell length, and total weight are highly correlated with one another, thereby providing reliable means of assessing meat yields from living snails. The mariculture of S. gigas is feasible, but because of the snails' slow rate of growth it may not be economically practical at this time. Perhaps local fisheries in the Caribbean Sea could be reestablished and/or maintained by seeding subtidal algal flats with hatchery-reared juvenile snails.