The Canadian Shield is an area of Pre-Cambrian rocks some 2,000,000 square miles in extent, which produces a half-billion dollars worth of minerals per year. The geophysical prospecting methods of most use here are magnetic and electrical. Geophysical methods, after recovering from an earlier period of disfavor, are now beginning to be properly appreciated by the local mining industry. Several examples of important recent geophysical discoveries are presented. Future expansion in this field appears inevitable.