A method of registering two or more localization systems utilizing unique coordinate frames A and B to a common coordinate frames includes measuring position information for one or more reference locations r in each coordinate frame (e.g., Ar and Br). For each reference location, a fiducial grouping is created from the respective position measurements (e.g., (Ar, Br)). The fiducial groupings are used to generate a mapping functionfthat transforms position measurements expressed relative to the second coordinate frame B to the first coordinate frame A. The mapping function f is defined such that a distance between f(Br) and Ar is about zero for each reference location r. Each localization system may also measure position information for a respective fixed reference localization element. Divergence between these fixed reference localization elements in the common coordinate system may be used to monitor, signal, and correct for anomalies such as dislodgement and drift.
