The Mother and Infant Home Visiting Program Evaluation (MIHOPE) is the national evaluation of the Maternal, Infant, and Early Childhood Home Visiting (MIECHV) program. MIECHV was authorized by Congress in 2010 and started a major expansion of evidence-based home visiting programs for families living in at-risk communities. The study is being conducted for the U.S. Department of Health and Human Services by MDRC with several other research organizations. MIHOPE includes the four evidence-based models of home visiting that 10 or more states chose in their initial MIECHV plans in fiscal year 2010-2011. To provide rigorous evidence on the MIECHV-funded programs' effects, the study randomly assigned about 4,200 families at 86 sites in 12 states to either a program group who received MIECHV-funded home visiting or to a control group who received information on community services. An earlier post in this series discussed considerations for reporting and interpreting cross-site impact variation and for designing studies to investigate such cross-site variation. An earlier report discusses how those ideas were applied to address two broad questions in the Mother and Infant Home Visiting Program Evaluation (MIHOPE): (1) whether variation in the way program services were implemented was related to variation in impacts across local programs, and (2) whether variation in the amount of services participants received was related to variation in impacts. Results from those analyses can be found in the MIHOPE 15-month impact report. [To view the earlier report, "Quantifying Cross-Site Impact Variation: Some Important Lessons," see ED601164.]