Nurses and doctors work together in hospitals as they provide care to patients. Nursing knowledge and practice are affected by relationships between nurses and doctors. This study sought to shed light on relationships between nurses and doctors using a broad comparative approach. Relationships between nurses and doctors in Britain and America were examined in order to shed light on the nature of the relationship between nursing and medicine in Britain and America between 1860 and 1914 and to elucidate factors which contributed to the development of this relationship. Examination of the historical roots of the relationship between nursing and medicine may help nurses to develop a deeper understanding of the situation of nursing within healthcare and the ways in which historical factors, such as societal practices and assumptions regarding class, gender, hospitals, and work have affected nursing theory, practice, and status. Studying these issues in two countries may facilitate exposure of factors which might be overlooked in a study of one country alone. This study focuses on hospitals in London and Philadelphia, which were both major centres for development in nursing and medicine during the study time period.The time period for this thesis is 1860 to 1914. It begins with the opening of the Nightingale School at St. Thomas's Hospital in London in 1860 which served as a model for other hospital training schools for nurses in London and Philadelphia. The bulk of the material for the study comes from the 1880s to the early years of the twentieth century as multiple formal hospital nurse training schools developed in important hospitals in both cities.Various factors were identified which contributed to the context in which nursing developed in London and Philadelphia during the study time period. This study examines conceptualisations of nursing and nursing work in relation to medicine and doctors' work particularly through Nightingale's writings and the elaboration of her ideas by her friend Eva Luckes, matron of the London Hospital as well as material in nursing textbooks. The study also looks at relationships between nurses and medical staff as they worked on hospital wards, particularly the effect of the presence of many medical students on the wards of London hospitals and their absence in Philadelphia. The importance of strong nurse leaders within hospitals in regard to separation of hospital nursing and medical services is examined. Harmony and discord between nurses and doctors is examined in order to understand factors which contributed to tensions between doctors and nurses. The case of the development of physiotherapy reveals important aspects of relationships between nursing and medicine in society.