An important debate has developed in the last few years on the subject of social participation, centered above all on the study of the forms of participatory democracy and the relations between the main subjects of it. Almost all the studies on participation bring out the role of cognitive resources and the risks of information asymmetries between the various subjects taking part in the planning. The setting up of information social systems in the welfare field too has been the most suitable response for avoiding this risk. However, not all the information systems guarantee the same level of participation, and so theory and the use of ideal types can be used to identify the various possible models and the type of participation preferred for each. only subscribers can see the full article