Modellansatz und -konzeption zur quantitativen Politikfolgenabschätzung für den biologischen LandbauJürnSandersauthorNicolasLampkinauthorStolzeMatthiasauthorMidmorePeterauthorAlthough organic farming has expanded significantly in Germany and Switzerland in the last decade, there is still a lack of a sectoral policy model that is able to analyse the impact of policy measures on organic farming. Equilibrium models and econometric models are considered for various reasons as rather inappropriate, whereas optimisation models in form of a sector-consistent farm group model seem to be a promising model approach. The bottom-up approach of this type of model makes it possible to analyse the impacts of policy measures on farm incomes and volume of production of organic and conventional farms at farm type, regional and sectoral level. Policy environments and social economy2005kassel university press GmbH, KasselConference paper, poster, etc.