Waste separation at companies is considered a priority to achieve a circular and sustainable society. This research explores behaviour change poli-cies for separating the organic fraction of municipal solid waste (OFMSW) at Small and Medium Enterprises (SMEs), particularly in cities. At SMEs, co-work-ers are responsible for waste disposal. Therefore, their behavioural intention to-wards pro-environmental action plays a major role. In this study, we have used agent-based modelling and simulation to explore the waste behaviour of the ac-tors in the system. The models were co-created in participatory workshops, sur-veys and interviews with stakeholders, domain experts and relevant actors. Ad-ditionally, we co-created and tested practical social and technical interventions with the model. We used the collaborative modelling method Lange reported to conceptualise, implement, test and validate the models. Five policies that affect waste separation behaviour were included in the model. The model and simula-tion results were cross-validated with the help of a literature study. The results were validated through experts and historical data to sketch a generalisable idea of networks with similar characteristics. These results indicate that combinations of behaviour profiles and certain policy interventions correlate with waste sepa-ration rates. In addition, individual waste separation policies are often limitedly capable of changing the behaviour in the system. The study also shows that the intention of co-workers concerning environmental behaviour can significantly impact waste separation rates. Future work will include the role of households, policies supporting separating multiple waste types, and the effect of waste sep-aration on various R-strategies.