Cannulation of veins and arteries is an important aspect of patient care for the administration of fluids and medications and for monitoring purposes. Establishing vascular access by a central venous catheter (CVC) in ICU patients is often technically challenging. However, being able to promptly and safely establish central access is a critically important skill for any acute care provider. The utilization of ultrasound guidance to guide vascular access, particularly central venous access, has been shown to improve first attempt success rates (Troianos et al., Anesth Analg 114:46, 2012; Lamperti et al., Intensive Care Med 38:1105, 2012) and reduce procedure-related complications such as pneumothorax, arterial puncture, and nerve injury (Bouaziz et al., Anaesth Crit Care Pain Med 34:65, 2015). In addition, ultrasound can also be used to prescan and choose the most appropriate vein for access (Saul et al., J Ultrasound Med 34:1301, 2015), check real-time location of the guidewire and/or catheter (Stone et al., Am J Emerg Med 28:82–84, 2010), and aid in early detection of puncture-related complications such as pneumothorax or hematomas (Lichtenstein et al., Intensive Care Med 25:383, 1999). Ultrasound guidance to place femoral or internal jugular venous access has been well documented and established in practice and will only be briefly reviewed. Using ultrasound to place catheters in the subclavian vein and radial artery will be reviewed in more depth.