Michael King was a Professor of Primary Care Psychiatry at UCL. Michael led and expanded the Department of Academic Psychiatry at the Royal Free Hospital from the early 1990s, steering its merger with UCL. He then became Director of UCL's Division of Psychiatry in 2014, establishing it as an international stronghold for psychiatric research and education.

Michael grew up in New Zealand and graduated in zoology, then medicine, before moving to the UK. He qualified as a GP, then trained in psychiatry at the Institute of Psychiatry before settling in North London. He had unrivalled intellectual curiosity which he applied across disciplines to advance understanding of mental health science. He was outspoken and direct which made him inspiring and great fun to work with.

Michael's research outputs were genuinely prolific. He produced almost 800 scientific publications before he died and was awarded millions of pounds of competitive grant funding. His expertise spanned clinical trials, epidemiology, sexual health and end of life care. The diversity of his research reflects the wide-ranging collaborations he generated. It seemed he could apply his enthusiasm to any aspect of psychological medicine. Everyone wanted to work with Michael. When junior researchers approached him he was always interested and keen to unpick challenging research questions. During his long career, he worked with leading researchers across the globe, from Australia and South America to India and Europe. His focus was always on designing the best science. And refreshingly, he was humble about his own achievements, more interested in delivering evidence that made a difference for patients and the public.

Michael's contributions to mental health are a challenge to summarise. Perhaps there are three key themes. Firstly he prioritised scientific rigour in mental health research, whatever the clinical question. He founded and co-directed the PRIMENT Clinical Trials Unit dedicated to robust methodology in primary care and mental health research. Secondly, he embraced cross-disciplinary approaches, moving away from traditional mental health silos. And thirdly, he trained and energised a huge cadre of future researchers. Multiple former trainees are now professors and senior academics in broad-ranging specialities, from intellectual disabilities to old age psychiatry, from psychosis to depression, from early determinants of mental health to end of life care, economics and social science. Former colleagues recount strikingly similar stories when remembering Michael; how he jump-started their career, be it their first study or publication, their promotion, their move to a new job at UCL or his genuine encouragement and delight when they succeeded.

He never shied away from uncomfortable questions in mental health. He led research highlighting inequalities experienced by people from ethnic minorities with psychosis, he critically evaluated complex interventions including talking therapies, he championed involving service users in research, and he excelled in applying state of the art statistical methods to large datasets and trials.

Michael was an out gay man from the 1980s, a challenging era in both society and medicine. He believed that visibility for gay people was the key to overcoming stigma and stereotypes. He applied his skills to generate high-quality evidence demonstrating the mental health inequalities experienced by LGBT people. He took these findings directly to the people who needed to hear them, calmly and authoritatively giving evidence to Royal Colleges, the Department of Health and the Church of England.

Michael's energy for life was mirrored outside work. He spoke four or more languages, ran faster than people decades younger than him, played tennis and devoured novels and politics. He always had an opinion and whether you agreed or disagreed, he was probably better informed and thinking more critically.

He developed a rare lung condition which eventually compromised his usual physical fitness and he died in the Royal Free Hospital in London from pleuroparenchymal fibroelastosis in September 2021.

Michael is missed by all of us who were lucky enough to know him and his death is obviously a huge loss for his life partner, Irwin Nazareth. They were a couple for 37 years, having met at the Gay Medical Association in 1984. Irwin is a Professor of Primary Care at UCL who is now working to improve understanding of the lung condition which took Michael's life.