Abstract: One embodiment is directed to an elongate instrument navigation system for conducting a medical procedure on a patient, comprising: an elongate instrument comprising an elongate body coupled to two or more discretely positioned magnetic steering nodes, the elongate instrument comprising an insertion length selected such that a distal portion may be inserted to reach a position of a targeted interventional structure within the body of the patient, and a cross-sectional size profile configured to be navigated through one or more tissue structures of the patient as the patient is positioned in an operating environment which may be characterized by a global coordinate system; a computing system operatively coupled to the elongate instrument and configured to present a control interface to an operator; and two or more magnetic field sources, each of which is controllably movably coupled relative to the patient by a robotic coupling assembly operatively coupled to the computing system; wherein in response to comman