Introduction:
The discussion on 'Sustainable Development' began after the submission of a report on the environment to the United Nations in 1987. This report, known as "Our Common Future," played a significant role in initiating global conversations and actions towards sustainable development.

Explanation:
Our Common Future, also referred to as the Brundtland Report, was published by the World Commission on Environment and Development (WCED) in 1987. The WCED was established by the United Nations General Assembly in 1983 to address growing concerns about the accelerating degradation of the environment and its impact on human well-being.

The report was prepared under the leadership of Gro Harlem Brundtland, the former Prime Minister of Norway. It aimed to provide a comprehensive analysis of the critical challenges facing the world in terms of sustainable development and to propose strategies for addressing them.

Key Points from the Report:
1. Definition of Sustainable Development: The report defined sustainable development as "development that meets the needs of the present without compromising the ability of future generations to meet their own needs." This definition emphasized the importance of considering social, economic, and environmental factors in decision-making processes.

2. Interconnectedness of Global Challenges: The report highlighted the interconnections between various global challenges, such as poverty, population growth, environmental degradation, and unsustainable consumption patterns. It emphasized that these challenges should be addressed in an integrated manner rather than in isolation.

3. Role of Technology and Institutions: Our Common Future emphasized the role of technology and institutions in achieving sustainable development. It called for the promotion of environmentally sound technologies and the reform of institutions at all levels to support sustainable practices.

4. Global Cooperation and Equity: The report stressed the need for global cooperation and solidarity to address sustainable development challenges. It emphasized the importance of equity, both within and between generations, to ensure that the benefits and burdens of development are shared fairly.

Impact and Legacy:
The publication of Our Common Future had a profound impact on global discussions and actions related to sustainable development. It popularized the concept of sustainable development and provided a framework for policymakers, businesses, and civil society organizations to work towards a more sustainable future.

The report laid the foundation for major international agreements and initiatives, such as the United Nations Framework Convention on Climate Change (UNFCCC) and the Sustainable Development Goals (SDGs). It also influenced the establishment of national sustainable development strategies and the integration of sustainability considerations into various policy domains.

Conclusion:
"Our Common Future," also known as the Brundtland Report, was the report submitted to the United Nations in 1987 that initiated the discussion on sustainable development. It provided a comprehensive analysis of global challenges and proposed strategies for achieving sustainable development. The report's impact and legacy can be seen in the subsequent international agreements and initiatives aimed at promoting sustainability.