[1] After his compulsory military service he performed his doctoral research at the Dijkzigt hospital, where he later became Chef de clinique [nl] of the psychiatry department.
[4][5] He obtained his doctorate in medicine at Utrecht University in 1962 under professor Henricus Cornelius Rümke [nl] with a thesis titled: "Een kritisch onderzoek naar de betekenis van monoamineoxydase-remming als therapeutisch principe bij de behandeling van depressies".
[6] During the anti-psychiatry-movement of the 1970s van Praag faced criticism from students and others who were opposed to biological psychiatry and psychiatric medication, which even lead to threats and police protection.
[7] In 1982 he moved to New York City where he became a professor of psychiatry at Montefiore Medical Center and Albert Einstein College of Medicine.
Van Praag has also worked on the search for biological markers for psychiatric syndromes.
In gesprek met psychiater Herman van Praag' was published by Dutch journalist and writer Tjerk de Reus (1971), on life, opinions and academic works of Herman M. van Praag, based on in-depth interviews during 2010-2011.
[3][16] He is close friends with neurobiologist Dick Swaab although the two disagree fundamentally on the role of the brain versus the totality of the human being.
[2][16] Since the end of World War II he has worn a Star of David on his wrist.
[4] After his retirement, he has written extensively on psychiatry, religion, and religiosity, including several books.