Exploration throughout KGHM International’s Victoria property in Sudbury, Ontario, occurred over an approximate 10-year period and resulted in the discovery of the Victoria Deposit. A variety of geophysical techniques were used with varying results to detect Cu-Ni-PGE-rich ore bodies at depth. Near-surface methods supplemented traditional mapping and geologic interpretation techniques to gain an understanding of property-scale depositional environments. The use of 3C borehole EM surveying facilitated the transition from a broad exploration program, which was based on surface geophysical signatures and geologic principles toward a targeted mineral definition campaign. The presence of off-hole features within several drillholes targeting a lesser massive sulfide lens identified a mass of strong conductors approximately 1 km deep. The drilling of thin-plate forward models derived from the borehole EMs resulted in the intersection of the Victoria Deposit. The tabular deposit has a downdip extent of more than 1500 m and remains open at depth. This significant discovery is an example of the opportunity that remains at depth within the Sudbury Basin, one of the world’s most prolific mining camps.