The Malay civet Viverra tangalunga is a relatively little known member of Borneo's carnivore community found throughout Peninsular Malaysia, Palawan, Sumatra and adjacent islands and Sulawesi. To investigate the basic ecology of this species and examine the potential impact of selective logging, a radiotelemetry study was carried out in the Ulu Segama Forest Reserve in Sabah, East Malaysia. From December 1995 to June 1997, home range, movement and activity data were collected on 12 study animals in a dipterocarp rain forest, and comparisons made between civets in a selectively logged and an unlogged site. Mean home-range size was 110 ha and did not differ between sites or gender. In areas of range overlap, radio-collared civets tended to avoid one another. Day beds were located on the ground and were associated with dense cover. Activity levels averaged 55% and were similar between forest types and gender. Most activity occurred from 18:00 to 07:00 during which mean activity was 81%. In a single day, males travelled further and covered a larger part of their home range than females. Roads and trails were used by both sexes, and roads were the only observed source of mortality resulting from vehicles. While density was higher in the unlogged forest, this species persists in both areas. The ability to survive in disturbed habitats might be influenced by the proximity of undisturbed habitat that served as a biological reservoir, or source of individuals to immigrate into the disturbed habitat.