The social organization of female mountain gazelles was studied at Ramat-HaNadiv Park, on Mount Carmel. The behavior of distinctly recognized individuals was studied by year-round observations. This is the first study that individually identified female gazelles in the field. It is acceptable to believe that the male gazelles hold their own territories, and that females alternate between them. This study focused on females and new details were found: Female gazelles lived in distinct groups whose composition remained constant throughout the year. New females did not freely entered the established groups. Group home ranges overlapped, but various groups replaced each other in the same area at different times of the day. Different groups tended to use different parts of the overlapping home range. In general, but especially in the summer the different groups largely avoided being synchronously together in the same area. The occurrence of two groups in the same area at the same time was a rare event and when it occurred, a high rate of agonistic interaction was observed between the groups. Hence, groups of female mountain gazelles hold and defend temporal territories against other female groups, in contrast the reports that only male gazelles hold territory and female groups move among them. Mean seasonal group size ranged between 3.4 and 6.4 and was largest during winter, when groups of females joined together occasionally and little between-groups agonistic interaction was observed. It is suggested that group size is affected by food availability and predation pressure. Deliveries occurred throughout the year, but mainly during the spring.