Health Impact Assessment (HIA)

Tools and methods

How to undertake an HIA

This section will draw on a number of case studies to briefly describe the theory and practice of carrying out an HIA. Many HIA guidance documents have been produced, from all regions of the world and we encourage you to use these for detailed work. While there is no single agreed method for undertaking HIA, a general pattern has emerged amongst methods and there is much overlap between them.

Guidance documents often break HIA into four, five or six stages. Despite the differing number of stages, it is important to note that there are no significant differences between the methods. Also, the theoretical stages often overlap and intermingle, and a clean separation is not often obvious in practice. The stages are:

The HIA procedure

Toolkits, guides, overviews and other helpful documents
Full text


13th International Conference on HIA (HIA2013)
2-4 October, 2013 - Geneva, Switzerland

Health indicators for Sustainable Development Goals

Choosing the right indicators of healthy development is important to measuring progress that is meaningful to human wellbeing.
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Health in the Green Economy

WHO's Health in the Green Economy series propose important health co-benefits for sector and health policy-makers, and for consideration in the next round of IPCC mitigation reviews.
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Health impact assessment of mining projects

Online course, in English and French

Contact us

We welcome feedback on this web site, please e-mail: hia[at]