Landuse, such as livestock grazing, has a major impact on the vegetation of semi-arid and arid ecosystems in southern Africa. Plant functional types and traits have proven to be useful tools in helping to understand the complexity of vegetation responses to landuse change, and to predict the impacts of landuse on the vegetation. Plant functional approaches were applied and tested in various studies of vegetation change along landuse intensity- and environmental gradients within the BIOTA project. In the Thornbush Savanna of Namibia, a monitoring tool based on plant functional types and Landscape Function Analysis (LFA) was developed in order to characterise the state of the rangelands. In a trait based study in central Namibia, the influence of different major habitat types was found to be important for patterns of plant trait responses along grazing gradients. In studies of trait composition under different landuse intensities in the southern Kalahari, fleshy fruited species were found to have decreased while poisonous and spiny species increased with increasing landuse intensity. Furthermore, it was observed that range condition influences plant life form composition. In the same study region, it was found that intensive sheep farming leads to an increase of animal dispersed plant species. A study of the seed bank composition in Nama Karoo rangelands of southern Namibia revealed varying patterns of seed distribution depending on seed size and microtopographical soil surface parameters. In the Succulent Karoo of South Africa, it was found that the recovery of vegetation on abandoned agricultural fields depends on landuse management practise, as indicated by the composition of plant growth forms and life history traits. The results of all these studies contribute towards improved monitoring and management of semi-arid and arid rangelands. Further studies of plant functional types and traits could provide valuable information with regards to the restoration of degraded rangelands.