The endemic bearded sakis Chiropotes satanas Satanas and Chiropotes satanas utahicki of south-eastern Amazonia are among the most threatened of this region's primates because of a combination of deforestation and hunting, and their apparent intolerance of habitat disturbance. Recent surveys at eight sites confirm that sakis are locally extinct in some areas where intense habitat fragmentation is exacerbated by hunting pressure, but also show that, in the absence of hunting, they can be relatively abundant in isolated forest fragments. Density was unexpectedly low in one protected area, however, which implies that caution is necessary for the planning of long-term conservation strategies. Well-protected forest fragments of reasonable size ( > 5000 ha) appear to have good potential for the protection of bearded saki populations. While many of the region's major landowners may thus make a significant contribution to the management of saki populations, land conflicts are a potentially serious problem for the long-term conservation of not just these primates, but the region's fauna and flora as a whole.