We summarize data on the breeding biology (based on seven nests) of the White-tailed Sabrewing (Campylopterus ensipennis; Trochilidae) at Tobago, West Indies. Breeding occurred during the dry season (February–April). Nests were placed 1.75–11 m high in small dicot trees, bamboo and palms in the forest interior, usually near streams. Two white eggs were laid in bulky (7–35-cm high), cup-shaped nests; one nest contained spines from a palm (Bactris sp.). The camouflaged nestlings were quiet. During the late nestling period, a female made 1.27 feeding trips/h (10.25 h of observation) to the nest; feeding sessions averaged 0.93 min with an average of 2.0 regurgitations/nestling, and recesses off the nest averaged 44.26 min. The female fed on arthropods and nectar, and vigorously defended the nestlings.