Of all development strategies, microfinance is probably the one that is the most concerned about its impact. Conversations about microfinance mostly focus on claims and evidence of changes in the lives of the poor. Going by the debates at conferences and in journals, one gets the impression that the microfinance industry is obsessed with its impact, i.e. changes in the situation of clients that can be causally attributed to the access and use of financial services. Most controversies have to do with the selection of the right variables, measurement issues, the dimensions and levels of impact and assessment methodologies. There is a wealth of impact evaluations. 1 The evidence is mixed with some studies confirming positive or negative effects on some metrics, but with every wave of experimental analyses – randomised or not – the complexity of causal linkages becomes ever more obvious between access to and use of financial services and changes in the welfare of individuals, households and villages.