Turning history's page on its deadliest conflict, countries came together in 1948 to heal a bloodied world. Following years of war, distrust and pain, nations elevated the physical and mental wellbeing of people to a new level, forging a global pact and purpose to safeguard and advance health for all. Lofty sentiment transformed into practical reality 75 years ago with the entry into force of the Constitution of the World Health Organization, and WHO's founding as the specialized United Nations agency dedicated to promoting human health. The WHO was given a unique mandate to advance the wellbeing of all people, and unique ability to convene all governments and partners at the same table. Fast forward to today, as the WHO celebrates its 75th anniversary year from World Health Day on April 7, this mandate and convening ability remain as vital as ever. At the same time, the world needs a renewal of this commitment to put the health of all people first, from our grandparents to our children born today and in the future. COVID-19, conflict, climate change and commercial causes of ill-health, like unhealthy foods and tobacco, offer real reminders of how precarious our lives are, and how, without constant commitment to advancing our collective wellbeing, the fortunes of vulnerable communities worldwide will remain at risk. A seminal line in the WHO's Constitution states "the enjoyment of the highest attainable standard of health is one of the fundamental rights of every human being without distinction of race, religion, political belief, economic or social condition." This has guided the WHO's work to promote, provide and protect health for all. There have been many achievements along the way. Among the best-known is the eradication of the ancient scourge of smallpox. Today, the world is on the verge of also eradicating polio, with annual cases reducing by 99.9 percent since the 1980s. Other successes include eliminating, or near-elimination of, five tropical diseases, making childhood immunization close-to-universal, and setting global standards for safe drinking water. Furthermore, the WHO has supported countries to adopt a landmark treaty on tobacco control, regulate aggressive marketing of breastmilk substitutes, and report on health emergencies with the potential of global spread. The WHO played a catalytic role in advancing the development and rollout of first-ever vaccines against Ebola and malaria that are now saving lives across Africa. The WHO's work in humanitarian settings has provided life-saving care to millions. The list continues. As WHO marks its 75th year, there is much that the Organization, and the countries that created it, can be proud of. But great challenges remain. COVID has shown how we, as a global community, are only as safe from pandemic threats as the least prepared nation. Too many people lack access to quality, affordable health services, instead suffering from preventable or treatable ill-health. Modern concerns compound this, like the impacts of the climate crisis that endanger millions from flood and drought, rampant air pollution, and the wanton misinformation and disinformation bedevilling people's health choices. There are also threats to people's wellbeing driven by factors beyond health, including conflict, economic and commercial. To meet these challenges, the WHO has been changing and adapting to deliver better today, and for the next 75 years. Our work focuses on five areas: improving the level of health of all people; ensuring everyone has equitable access to quality, affordable health services; protecting the world against novel and known pathogens; empowering science and scientific information to support good health; and strengthening the WHO to meet today's and tomorrow's demands. In COVID's wake, we are supporting countries negotiating a historic pandemic accord, rooted in the WHO Constitution, to prevent and respond to future pandemic threats collectively. Nations are also amending the International Health Regulations to make them relevant to a post-COVID world, and strengthening WHO's financial, governance and operational base for a safer and healthier world. The reasons for such measures are clear. COVID set back progress on achieving the health-related Sustainable Development Goals, and caused incalculable human, social and economic losses. So we must reclaim lost gains by redoubling efforts to make universal health coverage a reality for all, driven by primary health care, and strengthening national and global systems, from state-of-the-art surveillance to investing in country preparedness, to make a more secure world. The lifeblood of the WHO's work is science and evidence. Data-driven guidance remains core work, helping the WHO and countries invest resources where health needs are greatest. Access to evidence-based advice also helps people make sound health choices. This is critical today because, as COVID has shown, misinformation and disinformation has made decision-making even harder and, in extreme cases, deadly. The WHO has been transforming its operations to effectively implement work on all these fronts, and more, with a clear-eyed focus on delivering impact at the community level. Today, 75 years later, and after a new virus showed how vulnerable the world remains, the need for the WHO is as vital now as ever. If the Organization had not been created all those years ago, we would have to create it today. So on the WHO's birthday, I thank all countries and partners for their commitment to laying the WHO's foundations in 1948, and continuing to strengthen them for a healthier, safer and fairer future for all.