The recycling of plant-nutrients as nitrogen, potassium and phosphorus from human nutrition is considered to be a preposition towards sustainable agriculture. Commonly, human excreta are collected together with waste water and other liquid wastes from households and small industries. During the treatment in central sewage-works the valuable nutrients cannot be separated from potentially harmful substances such as heavy metals. Therefore, the application of sewage-sludge on agricultural fields is strongly limited. Today, in Germany a major amount of sewage sludge is burned in waste incineration plants. This means a dissemination of phosphorus, potassium and nitrogen into the atmosphere. Phosphorus and potassium fertilisers are extracted in mines and as such non-renewable. A shortage of phosphorus to be used as fertiliser is expected to arise within the next 80 years (STEEN, 1998). Alternative Sanitation Concepts such as the separate collection and treatment of urine and faeces prevent the contamination of the plant nutrients with potentially harmful or unwanted substances from other liquid wastes. The main feature of this concept is the use of a separation toilet. It can be used in the same way as any other common flushing-toilet but has a special valve for separate urine collection. The urine can easily be stored in containers e.g. in the basement of a house and used as fertiliser. A composting process ensures hygienisation of the solid faeces separated from flushing water. Due to its low content of nitrogen all remaining waste water can be treated in a constructed wetland. The studies introduced followingly were carried out within the scope of the SCST (Sanitation System of Separate Treatment) research project. This EU-Life demonstration project is a result of the cooperation of the KompetenzZentrum Wasser Berlin, Berliner Wasserbetriebe, Veolia Water and Anjou Recherche. It contains a setup of a complete Alternative Sanitation system including the conversion of 10 private households and two office-buildings as well as a biogasplant and a constructed wetland in Berlin-Stahnsdorf. It was the aim of the SCST-project to demonstrate the feasibility of an alternative sanitation system working with separation toilets. Apart from the technical questions to be answered it was necessary to know how urine and faeces are to be used in agriculture. The following four questions point out the aspects which needed to be investigated in detail: (i) How are the fertilising effects of urine und faeces compared to conventional mineral fertiliser? (ii) What impact has urine to soil organisms? (iii) How much gaseous nitrogen is lost after application? (iv) Would farmers and consumers accept urine as fertiliser? In this report you will find the four mentioned aspects investigated. This was done by carrying out laboratory or field experiments as well as acceptance SCST Final Report Task 8 – Fertiliser usage – Muskolus, Humboldt University of Berlin - 4 - studies for each of them accordingly. You will find a detailed description of the methods and materials used as well as the results and statistical evaluation as appropriate. Regardless of the advantages possibly reached by a treatment of urine in the presented studies it was assumed that pure urine was used. It is still not known what kind of processing is suitable to reduce the water content of urine or any unwanted substances and whether the energy input during the treatment is justifiable or not. However, some results of the studies followingly presented may change if treated urine instead of pure urine was used.