Nurses are often the first and last people to touch us. They are at the bedside of the sickest and most vulnerable; they give us good news and bad, and offer support, expertise, and connection in the darkest moments. Nursing is the oldest and most fundamental kind of health care, and today registered nurses are the largest portion of the health care workforce. Yet despite being recently celebrated (or even just finally recognized) during the Covid-19 pandemic, nurses are often undermined and undervalued in ways that reflect complications of gender, race, and class. In this book, journalist Sarah DiGregorio chronicles the lives of nurses past and tells the stories of those working today—scientists at the vital intersection of health care and community who are actively changing the world, sometimes invisibly.