This ensures that comparisons between groups can be made, which helps to reveal the different perceptions of the sectors and countries. It may be the case that participants from the water sector will describe water as "scarce", while those from the energy sector will share a different view. The overall purpose of this exercise is to reveal the extent to which the groups agree or disagree, and to show how each country and sector views a particular issue or issues. The sectoral and national presentations in particular are not given by external experts, but by the respective authorities or national representatives.