The kodkod Oncifelis guigna has one of the smallest distributions of wild felids, being geographically restricted to a narrow strip within Chile and Argentina. An investigation of population demography and habitat selection was carried out using trapping and radio-telemetry techniques in transitional Valdivian forest at two sites in southern Chile. The mean home-range size was estimated at 269 ha with considerable overlap of ranges and core areas giving a density of combined adults and sub-adults of 0.97/km2. Forest, thicket-forest, and scrub-thicket predominated in the ranges of most individuals and habitats at less than 50 m elevation were more frequently used than higher slopes. With the exception of páramo and thicket, all other habitat types were used more frequently than expected by at least one of the kodkods. The study confirmed the strong habitat association with Valdivian and Araucaria forests previously reported for this species, but also suggested a more flexible use of habitat within home ranges and individual preferences of habitat used as core areas. Flexibility in resource use and mutual avoidance may explain why kodkod ranges overlap and populations reach high densities locally. This high degree of adaptability may well be relevant to the long-term survival of this species in an ever increasing, anthropogenically-modified environment.