The popliteal sciatic nerve block is an effective regional anaesthesia technique for surgical anaesthesia and analgesia of the lower leg, foot, and ankle, sparing the medial leg, which is supplied by the saphenous nerve. The sciatic nerve divides into the tibial and common peroneal nerves in the popliteal fossa, making this block crucial for procedures such as Achilles tendon repair, foot surgery, and toe amputation. The block can be performed via posterior, lateral, or medial approaches, using landmark, peripheral nerve stimulator, or ultrasound-guided techniques. Ultrasound enhances precision by identifying the bifurcation and ensuring optimal local anaesthetic spread. Complications include vascular puncture, nerve injury, and haematoma. Continuous catheter techniques provide prolonged analgesia for major reconstructive procedures.