Despite the burgeoning of publications in nursing ethics, only more recently has empirical evidence on nursing ethics been published. How nursing ethics can be empirically studied as well as enriched by empirical data will be the focus of this paper. Two empirical studies will be briefly presented and their contribution to ethics discussed. The first one is a quantitative research project about nurses' ethical behavior in daily practice. Using an adapted version of Kohlberg's theory of moral development, this study tried to describe and explore nurses' responses to ethical dilemmas in daily nursing practice. The second study attempted to describe the specificity of residential palliative care. A qualitative approach was used to explore and describe the processes that take place on an inpatient palliative care unit, and the experiences of patients, relatives and palliative care team members. The analysis of the value of both research projects for ethics underlines the power of empirical understanding in the relationship between research and ethics. The need for integration of both qualitative and quantitative research methodologies is argued.