Sustainable husbandry systems for grazing animals (cattle and sheep) can be achieved by sustainable nutrient management (SNM). This implies the tuning of inputs to outputs of nutrients, to achieve and maintain optimum ranges of agronomically wanted and ecologically acceptable reserves of single nutrients in the soil. P is presented as the ‘boss cow of the nutrient herd’ and its optimum range of available reserves, in the Netherlands expressed as P-AL count, is quantified as a P-AL count of 30–55. SNM is elaborated into two scenarios. In both, output of milk and meat is compensated for by a P-equivalent input from concentrates. However, in the scenario ‘off-take manure’, on soils with a P-AL count greater than 55, all manure produced indoors is to be removed from the farm until the P-AL count is 55 or less. If large-scale manure processing is not a realistic option, the scenario ‘own concentrates’ can be followed. In this case, on soils with a P-AL count of 55–100, output of milk and meat can no longer be compensated for by a P-equivalent input from concentrates, so concentrates are to be produced on the farm. Furthermore, soils with a P-AL count greater than 100 need maximum sanitation by off-take of all plant produce, so grazing and manure application are no longer allowed. At the farm level, SNM is elaborated into a quota system for stocking rate (livestock units ha −1) and milk production (kg milk 4% fat ha −1). If applied on a national level in the Netherlands, SNM will extensify grazing animal husbandry through a reduction in stocking rate by 27–41% and in milk production by 16–34% in the scenarios ‘off-take manure’ and ‘own concentrates’, respectively. At the same time, livestock and milk quotas will be redistributed across regions and farms. Consequently, current surpluses on the annual P balance-sheet of the national grazing animal husbandry will turn into ‘shortages’, implying a gradual decline in excessive soil P reserves. In the scenario ‘off-take manure’, this is achieved by a more than 50% reduction in the import of concentrates and by the export of stable manure. In the scenario ‘own concentrates’, it is achieved by a complete replacement of import of concentrates by concentrates produced on-farm. In a similar way, SNM reduces the surpluses on the N balance-sheet of the national grazing animal husbandry.