In the modern age, No state is entirely self-sufficient. From this necessity, the ideas of regional and international co-operation emerged. Many international organizations have been formed. One of them is the United Nations. The United Nations was formed with a view to establishing world peace. Almost all countries of the world are member states of the United Nations. Bangladesh achieved the membership of the United Nations in 1974. Besides, there are different regional organizations, such as- SAARC, ASEAN, EU, G-7, OAU, OIC, Arab League etc. These organizations work collectively for the interest of their member countries. In class five, we have learnt about different agencies and organizations affiliated with of the United Nations. In this chapter, we will know about different organizations of regional cooperation along with their aims and functions. At the end of this chapter, we will be able to- explain the importance of regional cooperation; mention various aspects of cooperat...