HOST helps in acquiring new knowledge, providing insights into the sustainability impact of social and technological innovations, and mobilising people to learn together and scale up these niche innovations. To address these complex challenges, HOST removes existing academic silos and fosters inter- and transdisciplinary collaborations, offering an interdisciplinary approach centred around four transversal axes: analysing sustainability, mobilising people, governing change and transformative learning.

Analysing sustainability uses tools such as life cycle assessment, external cost calculations and labelling with a systemic lens. Mobilising people relies on techniques including data driven behavioural change, co-creation and participatory foresight. Governing the change involves understanding how decisions are made and how different people and groups can work together, looking at roles, responsibilities and practical ways to organise change to support smoother and fairer transitions. Transformative learning focuses on education and training on sustainability through bootcamps, retreats and the Factor 8 process.

Thematic expertise is clustered around five interdisciplinary topics, namely energy, mobility, economy, food and building, and four main drivers, namely climate, biodiversity, well-being and justice. In the energy sector, expertise spans multi-energy systems, positive energy districts, biomass, hydrogen and energy communities. In mobility, expertise covers urban mobility challenges, sustainable logistics and active mobility. In the building sector, circular building practices, eco-design and sustainable structural design and construction are combined. In the food sector, expertise ranges from agriwilding and agroecology to sustainable and healthy food consumption and food marketing. In the domain of economy, expertise spans the circular economy, labour economics, just transitions and consumer behaviour.