been manufactured in two main countries: Germany and Sweden (one company also manufactured them in China in sitting and squatting style but no information is available on whether this was a commercial success and if these toilets are still sold nowadays). In Germany, the company Roediger Vacuum sold the "NoMix" toilet between 2003 - 2011. However, this toilet did not become a commercial success, and manufacturing, sales and technical support ceased in about 2010 (the most prominent installation of Roediger toilets installed today is at the Swiss Federal Institute of Aquatic Sciences and Technology in Dübendorf near Zürich, Switzerland). Likewise, the Swedish company Gustavsberg stopped selling their urine diversion flush model in about 2011 which was regretted by many people because it was generally working well. In Sweden, urine diversion flush toilets are nowadays supplied by two manufacturers, Dubbletten and Wostman, which continue to sell their urine diversion systems today primarily for installation in summer houses in rural and semi-rural areas. These two types of urine diversion flush toilets have been installed in both research projects and community scale installations in Australia. The design difference between the various models is the shape and size of the two compartments and in the way the flush water is introduced for the two compartments. In addition, the Roederig NoMix toilet was the only toilet that was able to collect the urine pure - without any flush water - due to a valve on the urine compartment that was opened when the user sat down and closed when the user stood up and flushed the toilet. It was also this valve that caused a lot of maintenance issues due to struvite precipitation in this valve. In the other urine diversion flush toilet models, the urine is diluted with a small amount of flush water, usually about one litre per flush. The urine diversion flush toilet of Dubbletten features separate flushing with water in each of the two compartments. Urine-diverting dry toilets (UDDTs) Disadvantages It is unclear whether urine diversion (source separation) and on-site urine treatment can be made cost effective; nor whether required behavioral changes would be regarded as socially acceptable, as the largely successful trials performed in Sweden may not readily generalize to other industrialized societies. Disadvantages and challenges with urine diversion systems include: Social acceptance amongst users (detailed research on this aspect has been carried out by researchers in Sydney, Australia) User