The metal-detector is an electronic instrument; it is incapable of any independent act of free will. It is outside the reference of a system of good and evil : it is neither benign nor malign, ethical nor unethical, as neutral in such matters as a stone. It is capable merely of indicating the presence of certain objects on or below the soil. It bears no responsibility for human action consequent upon such indications. If this appears to be superfluous comment, it must be borne in mind that the very mention of the words ‘metal-detector’, with no reference at all to the machine's user, is guaranteed to raise the hackles of many archaeologists. Readers of this journal are surely aware of the wide range of archaeological opinion on metaldetecting; the issue of the relationship between orthodox archaeology and nietal-detecting has been aired at considerable length over the last few years and does not directly concern us here. Rather we intend to examine the practical application of the instrument to archaeological procedures.