This study investigates the complex dynamics of transnational security threats and the corresponding border management strategies at the Nigeria-Niger border, with a focus on cross-border crime challenges. The overarching theoretical framework employed in this
research is the Theory of Transnationalism, which emphasizes the interconnectedness and interdependence of countries in the contemporary global context. The study draws on a rich body of secondary data from various sources, including academic publications, government reports, international organizations, and non-governmental organizations. These sources provide insights into the multifaceted nature of cross-border crimes such as human trafficking, drug smuggling, arms proliferation, and terrorism, which have the potential to destabilize both Nigeria and Niger and have far-reaching consequences for the broader West African region. The analysis of the data reveals the intricacies of cross-border criminal networks, highlighting the role of porous borders, economic disparities, and political instability in facilitating criminal activities. In conclusion, this research underscores the importance of a comprehensive understanding of transnational security threats and the vital role of effective border management in addressing them. The findings contribute to the broader discourse on border security in the context of transnationalism and offer valuable insights for policymakers, security agencies, and international organizations working to combat cross-border crime and enhance regional stability in West Africa.