evidence: On July 23, 2022, World Health Organization (WHO) Director-General Tedros Adhanom Ghebreyesus, PhD, declared the current monkeypox outbreak a Public Health Emergency of International Concern (PHEIC), overriding the WHO Emergency Committee, which decided 6-9 against recommending a PHEIC.1 That decision was justified, with cases in more than 70 countries, most of which are nonendemic, many with no clear epidemiological links and milder nonspecific clinical presentation. The window for controlling monkeypox is closing and a well-funded global plan for containment is needed. [...] Since the International Health Regulations (IHR) were revised in 2005 in the aftermath of SARS, WHO has declared a PHEIC 6 times: for H1N1 influenza, polio, Zika, COVID-19, and Ebola (twice). Currently, WHO has declared 3 emergencies worldwide (COVID-19, polio, and monkeypox), placing major strains on national health systems. Monkeypox meets all IHR criteria for a PHEIC. Current clusters represent "an extraordinary event" as nontravel-associated cases have never been reported outside endemic areas of central and west Africa.1 Given the spread of MPXV to more than 70 countries in 6 WHO regions, this outbreak clearly constitutes "a public health risk to other States through the international spread of disease." Given the pace with which cases are being detected and the global scope, the risk that MPXV will become entrenched globally is increasing and "a coordinated international response" is essential.