This thesis explores the critical role of microvascular anastomoses in head and neck reconstructive surgery. It systematically reviews existing literature to compare outcomes between single and double venous anastomoses, highlighting that double anastomosis significantly reduces flap failure and venous complications. The study also evaluates the use of Microvascular Anastomotic Coupler Devices (MACD), demonstrating that these devices simplify procedures, save time, and improve surgical outcomes. The findings strongly advocate for double venous anastomoses and the adoption of mechanical coupling devices to enhance success rates in free flap reconstructions.