Nutrient control is generally acknowledged to be an important part of domestic wastewater treatment. However, it is not as widely recognised that nutrient control is only necessary due to the presence of urine in wastewater. With urine separation and a subsequent treatment or recycling, only solids and organic matter need to be removed for the treatment of domestic wastewater. Urine separation combined with recycling of primary and secondary sludge would make it possible to close nutrient cycles. Problems with pharmaceutics and hormones in the receiving waters would be alleviated. From a technical point of view, the separate collection of urine is possible with a so-called 'No-Mix'-Toilet: after separation the urine is stored in the household and in the night, when the sewers are more or less empty, it is led through the sewers are more or less empty, it is led through the sewers to the treatment plant. Just before it reaches the treatment plant, the urine must be collected and separately treated or recycled.