We deployed field researchers into communities in California, Mississippi, New York, Ohio, and Kentucky to delve into the intimate financial details of approximately 200 households. Over the course of a year, field researchers visited each family once or twice a month, logging detailed information about cash flows into or out of the households. This deep dive into how working Americans earn, save, and spend their money provides critical new input for conversations in realms from public policy to financial product design. At a time when the poverty rate is at a 15-year high, we aim to offer a fresh look at ways to tackle some of the nation’s most pressing social problems, rooted in clearer understandings of the struggles and strategies of low- and moderate- income families themselves.