René Ernst Nielsen, MD, PhD, is Professor of Psychiatry at Aalborg University and consultant psychiatrist at Aalborg University Hospital, Denmark. His clinical and research work focuses on affective disorders, severe mental illness, psychopharmacology, and the excess somatic morbidity and mortality seen in psychiatric populations. He is the new Editor-in-Chief of the Nordic Journal of Psychiatry, having previously served as associate editor from 2014 to 2024, and is also a member of the editorial boards of Bipolar Disorders, the International Journal of Bipolar Disorders, the International Journal of Neuropsychopharmacology, and others. He currently heads the Research Program for Affective Disorders and the Research Program for Mortality and Morbidity at Aalborg University Hospital and serves as national coordinator for the psychiatric network of Trial Nation. Internationally, he is President of the International Group for the Study of Lithium Treated Patients (IGSLI) and an active member of several collaborative consortia, including the ECNP Bipolar Disorders Network and PAN-Health. He has been principal investigator or national coordinating investigator on multiple large clinical trials in depression, bipolar disorder and schizophrenia, including studies of psilocybin, esketamine and algorithm-guided treatment. Dr Nielsen is the author of more than 120 peer-reviewed publications.