The World Health Organization is an agency within the United Nations. It works to protect the environment, promote healthy living, and help the most vulnerable. The WHO plays a significant role in global health improvement. It is responsible for leading global health issues, developing the agenda for health research, setting standards and monitoring health trends. With its members, the WHO develops policies and strategies for a variety of health problems. These include non-communicable disease and mental health as well as environmental and social health. In responding to international health emergencies like pandemics and natural disasters or humanitarian crises, the WHO plays an important role. The WHO is a tireless worker to improve world health. It sets standards and promotes research and provides technical support to help countries prevent, detect and respond to emergencies.