This study aims to understand how the health dimension is integrated into four impact assessment tools used in Geneva, Switzerland: environmental impact assessment (EIA), strategic environmental assessment (SEA), sustainability assessment (SA) and health impact assessment (HIA). We have chosen as a case study greenhouse gas (GHG) emissions reduction policies chosen by the city of Geneva. The methodological approach consists in analysing EIA, SEA, SA and HIA conducted on three projects in three topic areas: urban planning, heating and transportation. These projects are: a complex urbanisation plan in an urban neighbourhood in Geneva (the Gare des Eaux-Vives project), a sustainable transportation plan for a central district in Geneva (the St-Gervais transportation project) and a strategy to encourage the City's employees to use sustainable transport for local business travel. The results show some shortcomings in the consideration of health in SEA, EIA and SA. This work highlights a narrow vision of health in SEA and EIA, limiting itself to a review of the effects of projects on the determinants of the physical environment as required by the legislation relating to these tools. EIA does not require the integration of the health dimension. As for SA, our research found that health is treated much more superficially than in HIA and primarily through the analysis of 'health and safety' criteria. It appears from this work that HIA is the tool which provides the most elaborate assessment, compared to SA, SEA or EIA, of the consequences for health of the GHG reduction policies chosen by the local decision-makers of a city. However, our study suggests that the HIA community should identify the situations in which HIA should be carried out and in which cases it is better to include health issues within an integrated analysis.