Two-generation initiatives intentionally combine intensive, high quality adult-focused services with intensive, high quality child-focused programs to improve outcomes for children, primary caregivers, and families. The goal of integrating services for primary caregivers and their children is to achieve better outcomes than those accomplished by serving each generation in isolation (Chase-Lansdale and Brooks-Gunn 2014; Sama-Miller et al. 2017). Research suggests that to effectively support families, these services should be high quality, intensive, and intentionally aligned (Sama-Miller et al. 2017). This brief is the third in a series of three briefs that aim to support future evaluations in the field of two-generation approaches. This third brief highlights the experiences of four two-generation initiatives that used rapid cycle learning to test and refine strategies to strengthen service delivery. This brief is intended for two-generation service providers who seek to strengthen their initiatives, as well as their evaluation partners. (author abstract)