Healthcare professionals often encounter moral dilemmas in clinical practice that require increased responsibility and accountability for ethical decision‐making. This paper reports the results of a 6‐year longitudinal study that explored changes in moral judgement of five consecutive cohorts of occupational therapy (OT) and physical therapy (PT) students over the course of their professional training. The training programme included an ethics education component. The Defining Issues Test (DIT) developed at the University of Minnesota was used to measure moral judgement. A total of 548 students participated in the study. At entry into their professional training, the DIT scores of the OT and PT students were similar but higher overall than the norms established for college level students or for graduates from professional programmes in the DIT standardization sample. At the time of graduation, results showed no significant differences in moral judgement scores between males and females, their chosen programme of study (OT or PT), year of entry, or previous education. Comparing entry scores to exit scores from both programmes for 288 students who provided data at both times, we found that moral judgement scores increased significantly in both OT and PT students over the 2‐year programme of study. No differences were found in scores across gender, programme, year of entry, or previous education. Implications are discussed for including a formal ethics education component in the curricula of all health professional training programmes. Recommendations for future research are outlined.