The Building Bridges and Bonds (B3) is a national study that partners with responsible fatherhood programs to test the effectiveness of current and new strategies to support parenting skills, co-parenting, and employment among disadvantaged fathers. B3 will utilize an experimental design to provide needed evidence about program strategies. The project is funded by the Office of Planning, Research, and Evaluation within the U.S. Department of Health and Human Services. MEF Associates is a subcontractor to MDRC. MEF Associates staff members are involved in all aspects of the project including the identification of interventions to be tested, recruitment and selection of program sites, implementation of the random assignment designs, implementation research, and project reports.