Understanding mammal social systems and behaviour can best be achieved through observations of individuals in their natural habitat. This can often be achieved for large mammals, but indirect methods have usually been employed for small mammals. I performed observations of the striped mouse (Rhabdomys pumilio)during the breeding season in the succulent karoo, a desert of South Africa. The open habitat and the diurnal habit of striped mice, together with the use of radio-telemetry, made it possible to collect data on activity patterns and social interactions over an entire activity period (whole-day follow). The striped mouse in the succulent karoo has been reported to form groups of one breeding male, two to four breeding females, juvenile and adult offspring of both sexes, and several litters. Accordingly, daily range size did not differ between males and females, but females spent more time foraging whereas males spent more time patrolling territory boundaries. Captive R. pumilio display biparental care, and in this study both sexes visited the nesting site during the day, possibly engaging in parental care. Mice travelled more than 900 m/day, mainly during the morning and afternoon, and rested in bushes during the hottest times of the day.