The world faces old and new problems that are more complicated than our currently capable multilateral and national institutions. To face these challenges, international cooperation is becoming ever more important. An international environmental agreement is a kind of treaty that is binding in international law, allowing them to accomplish an environmental goal. Bilateral environmental agreement is defined as an agreement between two countries. If the agreement is signed between three or more nations it is called a Multilateral Environmental Agreement. These agreements, mainly drawn up by the United Nations, include issues, such as environmental policies, freshwater policies, hazardous waste and material policies, aquatic environment, wildlife conservation policies, noise pollution and nuclear safety. International agreements set a number of objectives: Informal agreements may formulate action plans for sovereign states or international institutions; they may establish or alter international organizations or bodies; and legally binding agreements may demand that sovereign states change their actions. Least developed countries face significant challenges in terms of mitigation and adaptation, which must be resolved by successful agreements. A state government may wish to abide by an agreement but lacks the power to do so. Some climate agreements build in frameworks for promoting implementation and enforcement through technology transfer, funding and technical support. Agreements can facilitate the process of forging a common vocabulary and a mutual knowledge of an issue. States have often taken steps within their own jurisdictions which foreshadow what they are prepared to agree internationally. The balance of power is increasingly shifting, giving rise to questions about the successful functioning of foreign regimes. This current multi-polarity also deepens cleavages over the nature of agreements. The financial crisis spurred consensus on institutional reform; adapting international architecture to better represent the dynamics of contemporary power. The emerging and developing economies have concluded agreements in the environmental problem field to promote mitigation and adaptation assistance to the least developed countries. This present paper analyzes the development, function and the problems of these agreements.