What exactly is public health law? Drawing from disciplines like epidemiology, public policy and evaluation, it's a field that we may not often think about in our day-to-day lives. But it has a profound impact on our lifetime trajectory. Sarah de Guia—chief executive officer of ChangeLab Solutions, a nonpartisan, nonprofit organization that uses the tools of law and policy to advance health equity—joins Contagious Conversations to discuss how to better engage communities to advance policy development, and how public health law can help facilitate true systemic change.