The topic of this final paper is the internal structure of the Customs Administration of Croatia using the example of the Customs Office in Pula. The introduction discusses the objectives, methods, and structure of the paper. The first chapter addresses the conceptual definition of the Customs Administration, outlining its functions, customs authorities, and the importance of the Customs Administration. The second chapter explains the internal organization of the Customs Administration, with a focus on the central office, regional customs offices, border customs offices, and customs officers and their roles. The third chapter, along with the fourth concluding chapter, focuses on the core of this paper—the Customs Office in Pula. It describes its structure and organization, including specific departments and their functions. The unique characteristics and operational specifics that make this office crucial for customs control in the region are highlighted. Problems and challenges are explored, including operational, technical, and administrative issues, and the contribution of the Customs Office in Pula to the economy and future development opportunities is emphasized, with a special focus on digitalization, international cooperation, and infrastructure modernization. Through a comprehensive analysis, the paper highlights the crucial role of the Customs Office in Pula in the efficient management of trade flows and its contribution to the economy, as well as opportunities for improvement and future development.