The functionality of the geometric microliths has been a commonplace in the prehistoric historiography since the very 19th century. During the last 30 years we can quote some researches on this subject, on isolated sites or partial series. Our PhD work was a major milestone that involved more than 700 pieces from Mesolithic and Neolithic sites located in the Ebro Basin. More of 350 of them come from Neolithic levels. They show an employment roughly limited to a third of the total, mainly as projectile elements.