The health care environment has experienced important changes in recent decades. However, processes of health care work have persisted in spite of these changes. These continuities are widely acknowledged but difficult to explain. This dissertation explores how processes of health care work persist through case studies of two academic medical centers, one located in Switzerland and the other one in California. Building upon a year-long ethnographic research in the internal medicine and surgery wards of both medical centers, it addresses different elements of persistence through five scientific articles. As a whole, this dissertation provides a model for understanding continuities in processes of health care work. It explains how training, hospital structures, change, and conflict contribute to these continuities.