Intensive methods of nutrition and husbandry for pigs and poultry have already been developed and implemented by the farming community over the last few decades. Similar intensive techniques in the nutrition and husbandry of cattle and sheep are currently being developed as a result of economic pressures, but their acceptability will depend upon consumer attitude as well as economic justification. The physiological, genetic and nutritional constraints on increasing animal productivity are briefly described, and biological and economic ceilings likely to prevail in the middle 1980s are presented, for each livestock class in turn. The major limiting factors to achieving biological ceilings are dealt with, and it will be shown that very different percentage achievements of maximum biological ceiling are likely to be obtained in practice. New possibilities for animal production in cattle and sheep are briefly considered. The implications of these advances in terms of human food production and natural resource utilization are discussed.