This week, Mark and Margaret take a look at some of the highlights from the shows of 2019, the year we celebrated ten years on the air. They revisit their conversations with Flint Michigan pediatrician Dr. Mona Hanna-Attisha on the water crisis, Campaign for Tobacco-Free Kids CEO Matthew Myers on the vaping crisis, and health care innovators like Dr.Tom Delbanco of Open Notes and primary care transformer Dr. Bodenheimer, and the show's 500th guest, House Majority Whip James Clyburn.