Eight aardvarks Orycteropus afer were fitted with radio-transmitters at Tussen die Riviere Nature Reserve between June 1996 and December 1997. Two became habituated and could be approached to a distance of 1 m. Activity patterns, home ranges and burrow use were investigated using telemetry and direct observations. In winter, aardvarks emerged above ground earlier, returned to burrows earlier and were active for shorter periods than in summer. They were nocturnal except occasionally in winter when some individuals foraged above ground before sunset. Home ranges varied between 133 ha and 302 ha and range overlap occurred within and between both sexes. Densities were c. eight animals per 1000 ha. Aardvarks used steep slopes (>15°) less than would have been expected according to availability. Average lengths of consecutive burrow use for three aardvarks were 4.9, 6.9 and 8.6 days, with some burrows being abandoned after only 1 day and one burrow being used for 38 days.