There is increasing interest in more extensive systems of livestock management, in response to the continuing problems of excess production, combined with concerns over the environmental consequences of intensively managed livestock systems. Therefore there is renewed interest in the role that legumes can offer, of which white clover currently has the greatest potential. White clover has been shown to have improved digestion and higher intake characteristics than ryegrass, but considerable losses of nitrogen can occur during the digestion process in cattle. It has been suggested that specific supplements such as rumen-degradable carbohydrates be offered to reduce these losses. While small scale experiments have demonstrated the potential for white clover to improve dairy cow performance, this has not always occurred in larger-scale system studies. Two such studies currently underway in Scotland and The Netherlands have not shown any consistent response to grass/white clover swards. Improvement in management, such as matching the nutritional requirements of the animals more closely to the growth pattern of mixed swards may help. A similar inconsistency in response has also been observed with beef cattle. Responses to clover with sheep systems can be obtained with relatively low clover contents, although to maximize animal performance, high clover contents appear to be beneficial.