From June 5 to 16, 1972, the United Nations convened the Conference on the Human Environment in Stockholm, Sweden, marking a historic milestone as the first global gathering dedicated to addressing environmental protection on a worldwide scale.

With over 1,300 delegates from 113 nations in attendance, the conference served as a pivotal forum to discuss contemporary environmental challenges and devise comprehensive strategies to address them.

It was during this gathering that the iconic slogan "There is only one Earth" emerged, resonating across borders and inspiring a collective commitment to environmental stewardship.

After the conference, two seminal documents were issued: the Declaration of the United Nations Conference on the Human Environment (commonly referred to as the Declaration on the Human Environment) and the Action Plan for global environmental protection, comprising 109 recommendations. These documents underscored the imperative for governments and individuals to collaborate in safeguarding and enhancing the environment for the well-being of present and future generations.

The Declaration on the Human Environment outlined seven fundamental principles and 26 common perspectives, delineating the rights and responsibilities of humanity concerning the environment. Emphasizing the protection and enhancement of the environment as a shared goal, underscored the integral connection between environmental preservation, peace, and socio-economic development worldwide.

In a significant move, the conference proposed the observance of World Environment Day, designated to raise awareness about global environmental issues and underscore the importance of environmental conservation. Following the conference's recommendation, the United Nations General Assembly established June 5 of each year as World Environment Day during its 27th session in October 1972.

In January 1973, the United Nations General Assembly took further steps in response to the conference's resolutions by establishing the United Nations Environment Programme (UNEP). Charged with overseeing the UN's environmental agenda, UNEP is tasked with promoting and coordinating environmental protection efforts both within and outside the UN system.

UNEP plays a central role in setting the thematic focus for World Environment Day each year, aligning with prevailing environmental concerns and global priorities. On June 5 annually, UNEP hosts commemorative events, releases an annual report on the state of the environment, and honors outstanding environmental initiatives through the "Global 500" recognition program.

World Environment Day serves as a poignant reminder of humanity's impact on the planet and underscores the imperative of environmental protection. It embodies the collective consciousness and commitment of nations worldwide towards addressing environmental challenges and striving for a sustainable future.

Since 1987, UNEP has also designated a different city each year as the focal point for UN-led outreach activities, amplifying the message of environmental awareness and action on a global scale.

Governments, civil society organizations, and individuals worldwide join in marking World Environment Day with diverse activities and initiatives aimed at promoting environmental sustainability and fostering a deeper understanding of humanity's interconnectedness with the natural world.

Through collective efforts and continued commitment, World Environment Day serves as a catalyst for positive change, driving progress toward a more resilient and harmonious relationship between humanity and the environment.