The breeding population of Cape Griffon Vultures Gyps coprotheres (CGVs) on the cliffs of the Waterberg Plateau has declined from an estimated 500 in 1939 to only eleven birds in 2004, and the species is now considered critically endangered in Namibia. In 2002, the Rare and Endangered Species Trust (REST) initiated a supplementary feeding scheme on the farm Uitsig, as part of a project to obtain and fit satellite-telemetry equipment onto some of the remaining birds. Three capture operations were performed, in January, March and April 2004, using a capture and release aviary designed by REST, and captive CGVs as decoy birds to lure the wild birds. Each capture had 1-3 processing teams. REST is now the first organization in the world to fit satellite "collars" or PTT harnesses onto CGVs. Radio-telemetry devices have been fitted to a further five African White-backed Vultures Gyps africanus (AWBVs) in the area. REST is also the first in the world to develop a capture aviary and mechanism of this nature and the first in Africa to catch and process such a large number of free-flying old-world vultures in one operation for extensive sampling. During the three operations, a total of 291 birds were captured. These include two of the last remaining CGVs from the Waterberg colony (one of which was recaptured during the third operation). Altogether 259 of the captured birds were ringed. All vultures handled were documented photographically, while a full set of mensural and other data was taken for 36 birds, and sex estimations done for 164 birds. No losses were sustained, and marked birds returned to the restaurant and into the capture aviary almost immediately after the captures. The success of the operation is ascribed to painstaking organization and preparation, good team work, the gradual habituation of the wild birds to the capture aviary, the practical design of the capture mechanism and subsequent refinements, and the thorough testing of the harness devices on captive birds.