While almost all states have begun Medicaid delivery system transformation, initiatives and programs geared toward upstream prevention and population health are limited and many are untested, especially in the area of payment strategies. AcademyHealth’s Payment Reform for Population Health project worked with Nemours to assist Maryland, Oregon and Washington in exploring possible pathways to Medicaid payment for upstream prevention strategies. This work resulted in a series of issue briefs highlighting several practical lessons and approaches that state Medicaid agencies and their partners can use to demonstrate both the how and why of making upstream investments.