Ethan Nadelmann studied at Harvard University and London School of Economics and was a lecturer at Princeton University. While at Princeton, Nadelmann’s work focused on drug policy, attracting considerable attention with his articles in Science, Foreign Affairs, National Review and many others. He also formed the Princeton Working Group on the Future of Drug Use and Alternatives to Drug Prohibition.

In mid-90s Nadelmann founded the Lindesmith Center, a drug policy institute that six years later became the Drug Policy Alliance, a group for drug policies "grounded in science, compassion, health and human rights.” As the Executive Director of the organisation, Nadelmann advocates for the application of harm reduction principles to minimize the public health effects of the War on Drugs.

In 2021 he launched Psychoactive, a podcast on drug policy, drug use, and drugs research featuring Nadelmann interviewing leading figures in current debates on drugs such as head of the US National Institute of Drug Abuse Nora Volkow, authors Michael Pollan and Andrew Weil.