AIM: We propose that the conceptual orientation of professional identity is a logical consequence of self-concept development by focusing on career and its meaning and presents a measurable set of concepts that can be manipulated to improve retention of student and registered nurses within health service. BACKGROUND: Although professional identity is a term that is commonly written of in nursing literature, its theoretical origins remain unclear, and available empirical evidence of its presence or ability to change is omitted from nursing research. SOURCES OF EVIDENCE: We present a professional identity pathway and explore the factors that influence professional identity throughout a career in nursing. DISCUSSION: Nurses' professional identities develop throughout their lifetimes, from before entering nursing education, throughout their years of study and clinical experience, and continue to evolve during their careers. Education is, however, a key period as it is during this time students gain the knowledge and skills that separate nurses as professional healthcare workers from lay people. CONCLUSION: Finally, a call for longitudinal studies of students to graduates, using conceptually derived and psychometrically proven instruments capable of detecting the subtle changes in the construct over time, is recommended. Further empirical research into the theoretical concepts that underline professional identity, and the factors that influence changes in this important construct in nursing, is required. Ultimately, the practical relevance of such research will lie in the potential it provides for enhanced nursing career support and improved workforce policies.