Seed dispersal of big-leaf mahogany (Swietenia macrophylla) and its role in natural forest management in the Yucatán Peninsula, Mexico. As part of efforts to design appropriate silvicultural methods for sustainable forest management of big-leaf mahogany (Swietenia macrophylla: Meliaceae) in natural mixed forests of Quintana Roo, Mexico, a study of seed dispersal of 11 mahogany seed trees was undertaken. Both small (50−74 cm diameter at breast height, dbh) and large (75−100 cm dbh) seed trees showed seed distributions that were skewed to the west, generally matching the prevailing easterly trade winds. Total mean seed production of trees in the smaller size class was one-half of that of the large trees. Maximum seed dispersal distance was 50 m in the westerly directions (NW−W−SW) and only 20−30 m in other directions. Total seed dispersal areas were 0.4 and 0.5 ha for the small and large trees respectively. These results are important for designing seed tree or shelterwood regeneration methods for mahogany; they provide guidelines for creating the size and spatial layout of an overstorey felling and site preparation treatment that would match the dispersal area.