This article provides a structured introduction to negotiation as a fundamental tool in contemporary conflict resolution, international relations, and strategic diplomacy. It outlines core principles such as BATNA, interests versus positions, agenda setting, communication framing, and multi-level negotiation dynamics. Using theoretical foundations and practical insights, the paper explores how negotiation functions within modern geopolitical crises, including hybrid threats, maritime disputes, and regional tensions in the Mediterranean. The article also reflects on lessons derived from European and Greek experiences in crisis management and dialogue initiatives. This work conceptually draws from training completed at the Gandhi-King Global Academy (USIP) while presenting an independent analytical perspective.