A country-wide survey revealed 32 territorial pairs (with at least 36 fledglings) in three separate locations (Fig. 1), i.e. Lauwersmeer (7), N- and NE-Groningen (21) and Flevoland (4). Despite a trough in the vole population, the number of breeding pairs and the breeding results were slightly better than in 1996 (Fig. 2). Mean onset of laying was 24 May (N=15), mean clutch 3.4 (N=l 1) and mean number of fledglings 2.2 (N=14, Appendix 1). The sexratio, based on data obtained during ringing, in 11 nests was 12 males and 11 females, A single case of bigamy was found in Groningen, where a male attended two nests (both resulting in three fledglings). Except for the nests in Lauwersmeer, which were located in natural vegetation (reedbeds and rough herbage), all other nests were built in farmland (13x winter wheat, 6x alfalfa and probably once oilseed rape). Without nest protection during harvest, all the farmland nests would have failed. Without the cooperation of farmers, nests of Montagu’s Harriers in The Netherlands would have little chance of survival. Interestingly, a male ringed as nestling on a protected nest in 1993, was photographed in 1997 near its nest only 400 m away from the natal site; the ring could be read when projecting the slides (Photo 1). Much attention was paid to the collection of prey remains, pluckings and pellets (Appendix 2). Common voles (including unidentified voles, which were probably also Common Voles) were numerically most important (Fig. 3), but passerines figured prominently in the diet, especially Meadow Pipit, Skylark and Yellow Wagtail (farmland birds) and Starling (abundant breeding bird at farms). The presence of high densities of farmland birds may be important in years of vole scarcity.