The Rock Pratincole Glareola nuchalis was studied on the Upper and Middle Zambezi fromMayto November 1986 and from April to December 1987. Altogether 1938 Rock Pratincoles were counted; their distribution was closely associated with the availability of breeding habitat. The first birds were seen in mid-August and the species was still present in December. They nested in loose colonies on midstream rocks separated from the shore by flowing water. Sixty-four clutches (mean clutch size 1,8 eggs) were found and 44 eggs measured (mean size 29,2 x 21,5 mm). The eggs were usually laid on bare rock less than 1 m above the surface of the water and were sometimes in shade. Both sexes incubated and the frequency of nest relief was greatest during the hottest times of the day. The responses of incubating birds to overheating were bill-opening, panting, dorsal-feather erection, holding the wrists away from the body, and belly-soaking. Non-incubating birds drank often and did not seek shade. After hatching the young sought refuge in rock overhangs and crevices. The important breeding sites in the study area were identified and possible effects of future hydro-electric schemes are discussed.