The US health care system assumes many things about patients: that they can take off from work in the middle of the day, speak English, have a working telephone and a steady supply of food. Because of that, it's failing many of those who are most in need, says Mitchell Katz, CEO of the largest public health care system in the US. In this eye-opening talk, he shares stories of the challenges low-income patients face -- and how we can build a better system for all.