Many social animals give special signals when they encounter a predator. Alarm calls in particular often have special properties suited to specific functions. and this clearly illustrates the adaptive nature of signal structure. Among artiodactyls the use of alarm signals is widespread. but most attention has been focused on the function of rump-patch displays and the specialized bounding gaits associated with them. In contrast, alarm calls have received little attention, even though a number of species give them, especially African antelope. One of these. the klipspringer (Oreotragus oreotragus), is particularly interesting because its alarm call is often delivered as a duet between a pair of monogamously mated adults. By duetting we mean an almost simultaneous rendering of the alarm call by both adults for one or more repetitions. Keywords: Namibia, Namib Desert, Kuiseb River, desert adaptation, desert environment, desert mammals, group size, sociality, distribution, habitat utilization, habitat preference, vigilance behaviour, animal behaviour, predation, predator-prey relationship, activity rhythm, animal accoustic, animal communication.