This chapter focuses on the impact that innovative financial services can have on poverty, vulnerability and deprivation. Such an analysis is central to our study as developmentally successful institutions must contribute to poverty-reduction. However, the definition of what is meant by ‘poverty’, how it might be measured and who constitute ‘the poor’ are fiercely contested issues. In this introduction we identify the meaning used in this chapter and discuss the influence of definitional issues on the analysis of poverty-reduction strategies.