The European Green Deal and the European Union's new Circular Economy Action Plan defined targets for 2025 and 2030 to build up a circular economy and society in Europe. As waste management plays a crucial role in a functioning circular economy, a number of measures and strategies are being implemented for this area. For this reason, it is of great relevance to understand the development of future waste quantities and compositions in order to make waste management systems sustainable. Therefore, this master thesis develops scenarios that represent future quantities and compositions of mixed municipal waste. Since this waste stream is complex due to its composition and history, it is necessary to identify and analyze relevant factors that influence the amount and composition of mixed municipal waste. In this context, influencing factors from the socio-economic and socio-demographic area, legal framework conditions, waste management strategies and megatrends are elicited. Based on these factors, trend-based scenarios are developed using quantitative and qualitative forecasting methods to represent the possible future developments of mixed municipal waste in Austria for the forecast period 2021-2030. The trend-based "status quo" scenario is based on the results of the quantitative forecast by using multiple regression and only includes the influencing factors population number, number of one-person households and the real GDP index. In addition, the "Circular Economy" scenario further considers non-quantifiable influencing factors, such as the change in values of society, qualitatively. In combination with the "status quo" scenario, it is possible to identify and present future developments of mixed municipal waste in Austria.