Few viable populations of western black crested gibbon Nomascus concolor remain in southern China and northern Indochina, where the species is endemic. We conducted village surveys in the Nam Ha National Protected Area in Luang Namtha Province, Lao PDR to assess presence and status of gibbon populations. Forest surveys used to verify gibbon presence and species identification confirmed village reports of gibbon populations in three locations, and sonogram analysis identified all as N. concolor. These represent an expansion in the known distribution of western black crested gibbon in Lao PDR and the only known populations to occur inside the national protected area system. Significantly longer times since gibbons were last reported were associated with villages with <50% forest cover and high human populations. Although village taboos regarding gibbon hunting were reported, hunting and trade were nevertheless identified as factors contributing to gibbon decline. Results indicated that increased community-based management, public education and enforcement are needed to maintain N. concolor populations and their habitat in Lao PDR.