Abstract: A method for detecting tampering with a dial of a utility meter is used with a meter of the type including at least one rotary dial having angularly spaced circumferentially arrayed indicia and an indicator, the indicator and said indicia being relatively rotatable by a gear train having at least one gear which rotates in unison with the dial in operation. The method includes emcoding the gear with a code which corresponds in a predetermined fashion with the indicia of the dial and anotating on the meter a predetermined key to the initial correspondence of the code with the relative position of the dial indicator. The invention extends to an apparatus for carrying out the foregoing method.