In the last two decades a considerable number of new hydrometallurgical processes have been developed and implemented in gold industry allowing the economical treatment of increasingly complex and lower grade ores as well as refractory ores. As a result, all over the world the production of gold has almost doubled in the last 20 years. In order to overcome the environmental problems caused by cyanidation, new leaching agents have been searched and new leaching techniques, particularly heap leaching, were developed for the treatment of low grade ores. The developments related with gold extraction from pregnant solutions include, carbon-in-pulp, carbon- in-leach processes, the use of resins and solvent extraction techniques. A considerable effort has also been made to treat refractory ores. With that purpose pressure oxidation, bacterial oxidation and more recently electro-oxidation have been investigated with good results as alternative techniques to the classical oxidative roasting. In this paper those developments are revised and considerable attention is given to the electrochemical treatment of refractory sulphide ores.