Industrial clusters are considered more resource- and greenhouse gas-efficient than stand-alone industrial plants, but clustering may also act as a barrier to radical changes required for deep greenhouse gas emission reductions. Here we explore how clustering in an energy-intensive chemical industry cluster may influence attainability of the deep emission reduction targets. Chemelot, located in the southeast of the Netherlands, was willing to collaborate and we adopt a qualitative system dynamics approach based on expert interviews and group model building sessions. We found that clustering may hinder reaching deep emission reductions by three reinforcing feedback mechanisms, or ‘traps’, related to: incremental changes; short-term focus; and companies acting alone. The system dynamics analysis also identified potential mechanisms to escape from these traps, notably: (1) increasing cluster autonomy; (2) activating public support; (3) promoting changes in the supply chain; and (4) attracting long-term investors. The findings can inform policymakers on how to steer industrial clusters towards deep emission reductions, and support industrial cluster decision-makers on both internal and external strategies. Key policy insights Industrial clustering may offer opportunities to accelerate deep greenhouse gas emission reductions, but it could also cause carbon lock-in because of increased physical and organizational interdependency, which favours incremental changes, short-term focus, and solitary actions rather than collective actions, at the cost of deep greenhouse gas emission reductions. To fully exploit the potential benefits of industrial clustering for greenhouse gas emission reductions, policies need to take into account the causal relations that operate in a self-reinforcing way to lock the cluster into high greenhouse gas emissions, and that can help escape them. A coordinating authority operating across the cluster is necessary to ensure effective collaboration within a chemical cluster so as to escape carbon ...