Norms and preferences for regulating fertility are continually changing, and contraceptive use—particularly modern contraceptive methods—are becoming more acceptable in many countries. MOMENTUM Country and Global Leadership undertook a study to understand country-level differences in couples’ concordance and the relationship between concordance and country position on the modern contraceptive prevalence rate (mCPR) S-curve. This package of materials from MOMENTUM Country and Global Leadership describes the study, presents case studies from Kenya and Togo, and discusses recommendations for how policymakers can use findings to create the space for movement from low prevalence of modern contraceptive use to rapid growth along the S-curve.