Various embodiments of a burr hole plug assembly offer significant improvements for allowing lead and/or cannula access through a burr hole drilled through a patient's skull in connection with a Deep Brain Stimulation system, and subsequent sealing of such burr hole. The various burr hole plug assemblies described: (a) accommodate various burr hole sizes and provide a secure fit in the burr hole; (b) accommodate various locations for lead positioning and adjustment; (c) allow the lead to remain in a static position when the burr hole plug assembly is placed; (d) protect the lead from fracture at the exit location of the plug; (e) remain flush with the skull to avoid skin erosion and to eliminate unsightly flange protrusion from the patients' skull; (f) adequately hold the lead in place over time; and (g) provide a selection of various types of burr hole plug assemblies and sizes for use by the implanting surgeon, thereby eliminating the need for surgeons to resort to custom plugs and plug assemblies made in the operating room specifically to fit a given patient.