This thesis is a study about nurses' working environment in an Icelandic hospital (LSH), and its relationship with nurse job satisfaction, nurse burnout and nurse assessed quality of patient care. The study focuses on ways in which nurses' working environment can be improved to meet increasing health care demands and nurse shortages with the ultimate goal of providing high-quality patient care. Previous studies show positive relationships between supportive management, professional autonomy, adequate staffing and good inter-professional relationships, on one hand, and nurse job satisfaction, nurse burnout and quality of patient care, on the other. The first part of the study is a cross-sectional survey among a large sample of hospital nurses using an instrument previously employed in international studies. The second part is a series of focus group interviews with a sub-sample of the survey to further expand the survey findings. The study shows that working environment factors and nurse job outcomes are favourable for Icelandic nurses compared to nurses in five other countries. In this study the most important predictors of better nurse and patient outcomes are managerial support at the unit level, adequate staffing and good nurse-doctor working relationships. It is suggested that intrinsic job motivation, independent nursing practice, high educational background and supportive working environment of Icelandic nurses may contribute to their quality of working life and the quality of care they give their patients. The major contribution to knowledge from this study is to re-emphasise the important role of supportive frontline management, adequate staffing and good nurse-doctor working relationships, and to indicate the importance of intrinsic job motivation. Five new sub-scales to the key instrument are revealed, and a revised model on key determinants of nurse and patient outcomes is developed. -