Objective To understand the prevalence of healthcare students’ witnessing or participating in something that they think unethical (professionalism dilemmas) during workplace learning and examine whether differences exist in moral distress intensity resulting from these experiences according to gender and the frequency of occurrence. Design Two cross-sectional online questionnaires of UK medical (study 1) and nursing, dentistry, physiotherapy and pharmacy students (study 2) concerning professionalism dilemmas and subsequent distress for (1) Patient dignity and safety breaches; (2) Valid consent for students’ learning on patients; and (3) Negative workplace behaviours (eg, student abuse). Participants and setting 2397 medical (67.4% fem...