The Volkswagen (VW) Dieselgate, which was made public on September 18th 2015, was a trigger for further discussions about the future of diesel in passenger cars, which still continues up to now in 2017. Since that point of time, diesel as a propulsion system is in a strong focus in the public and the media, but also in politics. Many European governments reacted promptly to the findings, that diesel passenger cars would be much more harmful to human health than expected before and announced to introduce strict measures to reduce emissions from (especially diesel) passenger cars. The starting point of the masters thesis is to highlight the European Unions (EU) strategy as well as country specific regulations to reduce emissions of passenger cars to get an overview about the different reactions caused by the Volkswagen Dieselgate and the various approaches to reduce emissions. ^A literature research points out that Austria with its high share of diesel passenger cars is still reluctant regarding the implementation of appropriate actions to reduce emissions for diesel-powered passenger cars compared to other European countries. The masters thesis answers the questions, if Austrian customers are aware of emission-reducing measures in other European countries and to which extent this information influences the buying behavior for diesel passenger cars especially under consideration that any of these measures could be introduced in Austria as well in the near future as some measures have already been discussed by Austrian politicians. Private customers were questioned via an online survey about their awareness and the influence on the buying-behavior. Salesmen from various Austrian car dealerships were also surveyed about their experience of changes in customer behavior. ^Another source of information are interviews with experts from the automotive industry, which have been also interviewed about their experience of changes in customer behavior and their opinion to emission-reducing measures. The expected outcome is that private customers are not aware of all mentioned activities and other ones will not even know about the Austrian measures to reduce the emissions of diesel cars. It is assumed that most private customers will not change their attitude towards diesel before any measures are really introduced in Austria. Their buying behavior will change more reactive than compared to fleet customers.