Studies of the occurrence and nesting habitat choice of waders were conducted at Finsefetene (1200 m a.s.l.), a high mountain sedimentation flat on the Hardangervidda plateau, South Norway during 1967-1984. Eight species occurred in the study area during the period, either regularly such as Calidris temminckii, Actitis hypoleucos, Charadrius hiaticula, Calidris alpina, or occasionally, such as Tringa totanus, Calidris maritima, Pluvialis apricaria and Phalaropus lobatus. The densities of the whole wader community on the sedimentation flat were related to the proportion of snow-free areas at Finse around 10 July, and on the date when Finsefetene becomes totally snow-free (DFSF). Of the eight species, only C. temminckii and P. lobatus were found to be positively correlated with the extent of snow-free area, while C. alpina and C. lobatus were positively correlated with DFSF. In low density years the nests were usually placed in the same locations, these obviously being optimal sites. The majority of C. temminckii nests were located in the two intermediate fen vegetation associations, and according to its availability the Caricion canescentis-nigrae was clearly selected for. Two other preferred plant associations on drier ground, Lactucion alpinae and Arctostaphyleto-Cetrarion nivalis, were also selected for. Nest location preferences for vegetation associations are also indicated for the other wader species, but the data on these are limited. Changes in river flow causing varying water levels in the surroundings are a pronounced ecological trait on Finsefetene. In years with a heavy spring flood many nests would be submerged. The location of the nests in relation to a so-called «Zero point», varied from 34 cm below to 210 cm above. In high density years the nests of the most common species, C. temminckii, were spread over most of the flat. In years with a late spring flood, after the nesting had started, some low situated nests were flooded. To visualize the wader community pattern, the distribution of the variable number and scattered nest locations were plotted on maps. Details in nest locations of C. temminckii are given for each year; for the other recorded species the map covers all years. The Finsefetene sedimentation flat proved to be a valuable high mountain habitat for wader populations on Hardangervidda.