The Strait of Gibraltar is the unique and narrow connection between the Mediterranean basin and the open Atlantic Ocean. One of the main features of this place is the strong topographic constriction that happens both in the horizontal and vertical dimension in conjunction with the presence of a two-layered counter-current circulation and strong inequalities of the tidal range at both sides. These differences in tidal amplitude induce intense barotropic and baroclinic currents which interact with the sharp sea-bottom topography in the main sill of the Strait to create internal waves in the Atlantic-Mediterranean Interface (AMI). This book presents a comprehensive review of the most recent findings, along with some directions for future research necessary to enhance our knowledge of the tidal influence on the inter-basin biogeochemical budget.