ABSTRACT: Institutional financial self-sufficiency (IFS) is necessary for a microfinance institution (MFI) to obtain the large amount of funds required to reach and benefit truly large numbers of the poor and poorest households. There is no necessary trade-off between serving large numbers of the poorest households and the attainment of IFS by an MFI, as proven by the case studies in this paper. Cost-effective identification of the poor and the poorest women is essential to maximizing the effectiveness and efficiency of providing microfinance services to them. If the service is not exclusively for the poor and the poorest, it should be operated separately for them to minimize leakage to the nonpoor. The total cost of efficient microcredit t...