The EU provides farmers with incentives to adopt Countryside Stewardship Schemes (CSS) using subsidies in the framework of the agri-environmental regulation of the EU (2078/92), now included in the more general regulation on rural development. In this paper, a case study of 36 farmers in the village of Bierbeek was carried out to investigate the determinants of the willingness to adopt a scheme involving taking care of arable field margins in particular. Bivariate and multivariate logit analysis confirmed not only the importance of personal, structural and financial factors, but also showed the importance of social capital. Farmers who are more open to both professional and non-professional contacts are more likely to adopt a CSS. Hence, government and extension agencies should undertake more efforts to involve farmers as much as possible in activities of a professional and/or non-professional nature to stimulate them to adopt sustainable farming practices.