The United Kingdom and other European Governments are increasingly calling for Health Impact Assessment (HIA) of policies in order to predict how they will affect the health of populations. Approaches to HIA can be characterised as broad focus (holistic, sociological, qualitative) or tight focus (limited, epidemiological, quantitative). HIA must add value to decision making and lead to better decisions than would have otherwise been made. The quality of HIA will be judged on its utility, its predictive accuracy and its process. HIA must be closely integrated with the decision making process. HIA may be undertaken in combination with Environmental Impact Assessment (EIA) or separately. HIA does not mean that health should take primacy over other policy goals but does ensure that health is considered.