We evaluated the effects of reinforcing multiple manding topographies during functional communication training (FCT) to decrease problem behavior for three preschool-age children. During Phase 1, a functional analysis identified conditions that maintained problem behavior for each child. During Phase 2, the children's parents taught them to request positive reinforcers (attention or toys) via vocal manding, manual signing, or touching a picture/word card with or without a microswitch recording device. A non-concurrent multiple-baseline design across children was used to evaluate FCT outcomes. Results showed that problem behavior decreased for all three children. Results also indicated that the children initially used multiple manding topographies but displayed a preference for vocal manding over time. (Contains 3 figures.)