In 2017, the United Nations General Assembly convened a conference to consider a treaty on a complete ban on nuclear weapons — including their manufacture, possession, use, transfer, and testing. On July 7, 2017, 122 countries voted to adopt the Treaty on the Prohibition of Nuclear Weapons, with one abstention and one vote against. The treaty required 50 countries to ratify it to enter into force. That target was reached on October 24, 2020, when Honduras ratified the treaty; it was just a single day after Jamaica and Nauru had done so. On January 22, 2021 — 90 days after the fiftieth ratification — the nuclear ban treaty will enter into force. From that day onwards, all aspects of nuclear weapons will be illegal under international law. Nuclear weapons will join the other infamous weapons of mass destruction — chemical and biological weapons — as being illegal. One of the most salient aspects of the nuclear weapons ban treaty is that its motivating factors included not only “the catastrophic humanitarian consequences that would result from any use of nuclear weapons,” but also the vast and lasting damage to human health and the environment caused by nuclear weapons production and testing, with disproportionate impacts on women and children. Nuclear weapons, the treaty says “…pose grave implications for human survival, the environment, socioeconomic development, the global economy, food security and the health of current and future generations, and have a disproportionate impact on women and girls, including as a result of ionizing radiation.” It also notes the devastating impact that nuclear weapons testing has had on indigenous peoples. I am happy to report that IEER’s work had a role in some aspects of the treaty, notably regarding the humanitarian aspects of their production and testing. Our partnership with the 1985 Nobel-Prize winner International Physicians for Prevention of Nuclear War (IPPNW) in the late 1980s and the 1990s resulted in three detailed books...