This paper examines different barriers to formal saving, considering various interventions and their possible effects at microeconomic and macroeconomic levels. It presents a comprehensive review of the literature, based on a detailed classification of the barriers associated with supplyside factors, related to access to financial products, and demand-side barriers, related to the use and frequency of use of those products. The paper concludes that this classification and analysis contributes to a fuller understanding of the question of financial inclusion, and how to achieve it.