Arterial access is essential in resuscitation of trauma and hemorrhagic shock patients and can be effectively used for rapid endovascular treatment such as resuscitative endovascular balloon occlusion of the aorta (REBOA) and interventional radiology (IVR), continuous invasive hemodynamic monitoring, and frequent blood tests. In the REBOA procedure, obtaining an arterial access is the first and most critical step. Arterial access can be obtained in three ways: i) blind/landmark technique, ii) ultrasound-guided technique, or iii) surgical cutdown technique. Regardless of which technique is chosen, it is crucial to recognize external landmarks before implementing any technique.