Sand dunes are one of the critically endangered habitats in Europe. This vegetation type is under a strong anthropogenic influence. Its natural value is very high since many plant species with a narrow distribution are found there. The classification of Serbian sand-dune vegetation and the status of the described associations has not been validated by numerical analyses. This research presents an evaluation of sand-dune vegetation in Serbia on the basis of literature data, as well as new relevés. Psammophytic vegetation in Serbia was classified into two alliances, annual and ruderal Bassio laniflorae-Bromion tectori and perennial Festucion vaginate. The aim of this research was the classification of the alliance Festucion vaginatae, perennial, drought-tolerant, tussock-forming vegetation on sand. As proposed by OptimClass, Jaccard distance and flexible beta data (ß=-0.25) were used for the classification. Classification results were confirmed by detrended correspondence analysis (DCA) ordination. The result of the classification established that only two associations, Alysso gmelini-Festucetum vaginatae and Festucetum vaginatae, are present in Serbia. These associations are divided into groups that mostly correspond to traditional subassociations. [ABSTRACT FROM AUTHOR]