Assessment of student learning in complex areas is challenging, particularly when there is interest in students' deeper understanding and connectivity of concepts. Assessment of ethics learning has been limited by lack of consensus regarding what is effective and an overfocus on quantification at the expense of clinical or ethical relevance. Cognitive maps provide one means to evaluate depth and personal meaning of students' ethics knowledge. A pre-/post-test design using cognitive maps and the structure of observed learning outcome (SOLO) taxonomy was used to assess student learning on completion of a six-week intensive ethics course. Thirty-seven students completed the research. Student learning was supported by significant changes in component (content, labelling, relationships and structure/visual message), and total pre- and post-test cognitive map scores, and significant change in pre- and post-test SOLO scores. A strong relationship was found between cognitive map improvement and SOLO improvement. Student written commentaries describing their post-test cognitive map provided a richer, more elaborated account of their understanding that qualitatively enhanced their cognitive maps. Cognitive maps offer an alternative to traditional ethics assessment strategies.