In October 1993 an international workshop on nitrogen leaching in ecological agriculture was held at the Royal Veterinary and Agricultural University in Copenhagen, Denmark. This paper summarizes the discussion at the workshop and outlines recommendations and conclusions. The paper identifies key factors of major importance to a consideration of nitrogen leaching from ecological agriculture. These are: the farming systems approach: management of nitrogen resources at the farm and field level; the research methodology adopted to study nitrogen leaching; and finally the need to consider the problem of nitrogen leaching from a rotational perspective taking account of the heavy reliance on N fertilizers of conventional systems, which in turn leads to environmental, social and ethical problems. It is recommended to emphasize research work aimed at improving and developing ecological farming systems, in order to improve the ability of ecological agriculture to meet defined agronomic, economic, environmental, social and ethical criteria. Furthermore, it is recommended to encourage initiation of research in nitrogen supply and cycling in ecological farming systems and to organize further workshops aimed at intensifying cooperation and exchange in research work. It is concluded that there is a considerable potential for ecological farming systems to offer a viable approach to limit nitrate leaching whilst also meeting the requirements of broader goals of sustainability.