Porphyry copper ores and gold-bearing sulphides are significant contributors to overall world gold production. Flotation is the principal process for pre-concentration of the sulphides, for subsequent smelting, roasting or hydrometallurgical treatment. Lakefield Research has had the opportunity to study ores from many large deposits, both new discoveries and existing operations. Research was aimed at improved metal recoveries by applying new concepts in flowsheet design or by introducing more specific flotation reagents. This paper highlights the variability of porphyry copper deposits that have been tested and suggests mineral processing techniques that can be used to overcome the effects posed by the different ore matrices. Some of the innovative flotation practices are discussed.