Systems theory defines leverage points as places to intervene in order to change a system. Points with high impact on system behavior are notoriously hard to act upon, and indeed most policy intervention is based at the lowest level (#12 in Donella Meadows' order), via subsidies, taxes, or standards. This thesis explores how some of our most pressing issues, especially climate, biodiversity, or inequality, could be effectively solved using "action levers", coordinated action on multiple leverage points, like mindset (#2), system goal (#3), power to change system structure (#4), or rules (#5). Three action levers are identified, explored and partly tested: Negative Emissions, Sufficiency, Deliberative Democracy.

If suitably governed, Negative Emissions could reverse their current effect of extending the fossil era and its power relations and, while limited to perhaps 10% of current emissions, significantly accelerate decarbonization - a beneficial case of the "tail wagging the dog". We modeled two cases, Switzerland and global aviation, and found that an effective 1.5°C-compatible climate policy is affordable and accelerates today's strategies by more than a decade. Through a polluter-financed public fund, investing in nature-based solutions with biodiversity and societal co-benefits, several defining elements of society could be durably changed: democratizing governance, transferring wealth from corporations to communities, avoiding technological lock-in, and building purpose and identity. To test implementation with today's laws, we are preparing a voluntary 1%-scale pilot fund.

Sufficiency is central to any sustainable society. Since May 2022, as part of the SFOE SWICE project, frameworks for wellbeing, human needs, provisioning systems, and resource use were developed, to ensure consistency of the whole consortium, including its living labs. Furthermore, qualitative analysis of attitudes towards sufficiency has been conducted in stakeholder workshops. This will be the basis for quantitative analysis and modeling, building on this thesis - aiming to rethink the Swiss habitat, its satisfiers and provisioning systems, towards wellbeing for all with a much lower resource footprint.

Deliberative Democracy, in countless citizens' assemblies since the 1980s, reached remarkable convergence on complex topics linked to values, impacting human lives. However, it proved difficult to engage the population which has not participated in the assembly. On this foundation of active learning and facilitated deliberation, where knowledge and shared values emerge, we developed the theory, process, and IT tools of a universal "Academic Citizens' Assembly". It has been successfully conducted five times, with 20-200 participants, online and in three cities, on topics like energy, food, health, sufficiency, and climate policy, with final convergence >80% on the main proposals. A commune-scale assembly is in discussion for 2024.

Outreach to citizens and policymakers was developed for all policy-relevant results. Several limitations remain: the role of fossil fuel bans, needed public investments, quantification of a transition towards sufficiency, or how to build acceptance and integrate deliberative assemblies into the political system. Still, the conclusion is clear: the three action levers can be effective, and reinforce each other.