The dissident academic, Zhores Medvedev, author of books on T D Lysenko, agriculture, the 1957 nuclear accident in the Urals and the political use of psychiatry to quell dissent, has died. Here, his friend of many years, Professor Margot Light, reminds us of his contribution to our understanding of Soviet science.

Zhores Medvedev, who died on 15th November on the day after his 93rd birthday, first came to international prominence when he was incarcerated in a psychiatric hospital in May 1970, in response to his samizdat publications criticising the pseudo-science of Lysenkoism. He had already been dismissed from his post as head of the department of molecular biology at the Institute of Medical Radiology in Obninsk. His sojourn in the psychiatric hospital led to the publication in the West of an account, co-authored with his twin brother Roy, of the use made by the Soviet authorities of psychiatric hospitals to silence dissidents (A Question of Madness, 1971). In 1973 he was unexpectedly allowed to accept a 12 month research fellowship at the National Institute for Medical Research in London. Soon after his arrival in the UK, he was informed that he had been deprived of Soviet citizenship. It was restored in 1990, but Medvedev continued working at the NIMR until he retired in 1991. Despite being an active scientist, he found time after hours to research and publish books on Soviet Science (1978), The Nuclear Disaster in the Urals (1979), Soviet Agriculture (1987), and The Legacy of Chernobyl (1990). He also wrote political biographies of Andropov and Gorbachev. Medvedev remained physically and intellectually energetic until his death, cultivating vegetables on his allotment and writing every day. Medvedev remained physically and intellectually energetic, cultivating vegetables on his allotment until his late eighties (and then in his garden) and writing every day. In January he concluded his 115-chapter memoir, and shortly before his death he had completed Chapter 15 of a book on longevity.

Obituary: Dissident academic, Zhores Medvedev, dies aged 93