The colonisation of mobile sand dunes in the Veluwe, the Netherlands, was studied, as well as the spontaneous development of the vegetation into pine (Pinus sylvestris) forest. Three permanent plots were established, A, B and C, respectively, representing initial and transient stages of the succession. A list of the species is presented, and the abundance of each species in each separate plot is estimated. On account of these data the participation of higher taxonomie groups of species in each stage of the succession is described. It appears that lichens and soil algae appear first on mobile sand dunes, soon to make place for a vegetation consisting of herbs. These in turn suffer a temporary decline once the pine forest develops and forms a closed canopy. Their abundance increases again until the forest is about 100 years old. Then, slowly, bryophytes take their place. The flora on the Veluwe sand dunes is poor in species, as compared to the coastal dunes in the Netherlands. This is ascribed to the acidity of the extremely nutrient-poor soil.