Many human services programs are designed such that individuals must make active decisions and go through a series of steps in order to benefit from them - from deciding which programs to apply for, to completing forms, attending meetings, showing proof of eligibility, and arranging travel and child care. Program designers often implicitly assume that individuals will carefully consider options and make decisions that maximize their well-being. But research in the area of behavioral economics has shown that human decision-making is often imperfect and imprecise. People - clients and program administrators alike - procrastinate, get overwhelmed by choices, and miss important details. As a result, both programs and participants may not always achieve the goals they set for themselves. Insights from behavioral economics, which combines findings from psychology and economics, suggest that a deeper understanding of decision-making and behavior could improve human services program design and outcomes. Principles from behavioral economics can both shed light on decision-making and offer new tools to improve outcomes for program participants. For example, small changes in the environment can facilitate desired behaviors, planning and commitment devices can be used to improve self-control, and default rules can produce positive outcomes even for people who fail to act. The Behavioral Interventions to Advance Self-Sufficiency (BIAS) project was the first major opportunity to apply a behavioral economics lens to programs that serve poor and vulnerable families in the United States. The purpose of the project was to apply behavioral insights to issues related to the design and implementation of social service programs and policies. The ultimate goal was to learn how tools from behavioral science can be used to improve the well-being of low-income children, adults, and families. BIAS was led by MDRC in collaboration with academic behavioral science experts. In the first two years of the project, the BIAS team developed a strong base of knowledge of the existing behavioral economics literature and the needs of human services programs. The team engaged in detailed conversations with stakeholders from the academic, policy, and practitioner communities, created a glossary of behavioral interventions from a review of select field experiments, and hosted a Peer Practicum during which program administrators from across the nation joined with behavioral experts to explore the application of behavioral economics to ACF programs. The BIAS report "Behavioral Economics and Social Policy: Designing Innovative Solutions for Programs Supported by the Administration for Children and Families" describes insights from these early stages of the project. Following this knowledge development phase, the BIAS team worked with select ACF programs to diagnosis program challenges using a behavioral economics lens and design and test behaviorally informed interventions. BIAS conducted 15 random assignment tests in seven states with nearly 100,000 sample members. Projects ranged from work to increase child support collections, to improving child care recertification processes, to changing the messaging around TANF participation. The results of these tests demonstrated the promise of applying insights from behavioral science to improve human services program outcomes.