For over a decade now, Nigeria has been plunged into various kinds of insecurity. This started with insurgency in the North East and parts of North Central, then it was farmers-herders "clash" in North Central extending to the South, kidnapping and then "armed banditry" in the North West. This is not to mention the agitations in the South for secession and resource control.Consequently, Nigeria is overwhelmed with security challenges. It is also alleged that there is a kind of compromise, which stems from lack of political will to ensure peace and security. Thus, this book aims at looking into some alleged reasons for insecurity in Nigeria and emphasis on the responsibility of the international community bearing in mind the aim of the United Nations (UN) as seen in its Charter. The work, therefore, highlights various challenges bedevilling security in Nigeria. It argues that the international community is responsible in restoring international peace and security, since it is apparent that the challenges constitute a breach of international law, which defeats the aim of the UN; peaceful coexistence.