The book traces the evolution of major events of international relations during the 19th, 20th and a part of 21st centuries. The emergence of independent states in Asia and Africa in post-colonial period and their impact on inter-state relations are wide-ranging. . The book provides insights into rivalry and power play of strong nation states in influencing global and regional events including some of the ongoing intractable conflicts in many parts of the world. The September 11, 2001 terrorist attack on the soil of the US and the Iraqi war by the US in 2003 have brought about dramatic changes in international relations and international law. This book contributes to the understanding of causes of regional and international events at the beginning of the 21st century which has been often described as “Asian Century.”The book also describes Bangladesh’s foreign policy and its contribution to establishing a world of peace, harmony and prosperity. The book argues that no state, not even a powerful one, can alone address the challenging global issues of the day. It needs to work with other states, in multilateral institutions including the UN, to effectively resolve issues, such as terrorism, migration, environment, health, poverty, hunger, disease, gender-equality and empowerment of women, organised crime and drug trafficking.The book is useful for students, teachers, lawyers and foreign policy experts.