Prior to the widespread availability of point-of-care ultrasonography, invasive medical procedures were performed by the “landmark method”.  Landmark methods are based on surface anatomy, palpation, and sometimes trigonometry, and are fraught with the potential for error.  Complications, while unquantified in the misty past, were likely much more common than in the current era of readily available bedside imaging.  Vascular access procedures are inarguably safer and more successful when guided by sonography, but interpretation of ultrasound images still requires an understanding of both surface and deeper anatomy to relate the two-dimensional screen image to three-dimensional reality.  Further, there are circumstances where either the urgency of the resuscitation, or compromised access to the patient, requires that vascular access be obtained using landmarks rather than real-time imaging.  In such cases a detailed understanding of regional anatomy is critical to maximize procedural success and minimize complications.