Despite nursing's enthusiastic endorsement of the applicability of qualitative research approaches to answering relevant clinical questions, many nurse researchers have been hesitant to depart from traditional qualitative research methods. While various derivations of phenomenology, grounded theory, and ethnography have been popularized within qualitative nursing research, the methodological principles upon which these approaches are based reflect the foundations and objectives of disciplines whose aims are sometimes quite distinct from nursing's domain of inquiry. Thus, as many nurse researchers have discovered, nursing's unique knowledge mandate may not always be well served by strict adherence to traditional methods as the "gold standard" for qualitative nursing research. The authors present the point of view that a non-categorical description, drawing on principles grounded in nursing's epistemological mandate, may be an appropriate methodological alternative for credible research toward the development of nursing science. They propose a coherent set of strategies for conceptual orientation, sampling, data construction, analysis, and reporting by which nurses can use an interpretive descriptive approach to develop knowledge about human health and illness experience phenomena without sacrificing the theoretical or methodological integrity that the traditional qualitative approaches provide.