Background: The present study was aimed at investigating working memory (WM) and executive functions capacities in individuals with Williams syndrome (WS) as compared with mental-age matched typically developing (TD) children. Method: In order to serve the study goal, a sizeable battery of tasks tapping WM as well as attention, memory, planning, categorisation, shifting and inhibition abilities was administered to 15 individuals with WS (mean chronological age of 19.11 and mean mental age of 6.10), and to a group of 15 TD children (mean chronological age of 7.6 and mean mental age of 6.9). Results: Participants with WS showed deficits in both verbal and visual-spatial modalities for selective and sustained attention, short-term memory and WM, planning and inhibition. However, considering categorisation and shifting abilities, relatively unimpaired performance emerged on those tasks relying on verbal materials. Conclusions: These findings are both relevant to improve our knowledge about certain qualitative aspects of the anomalous cognitive development in WS as well as for its eventual clinical implications.