The electrowinning of copper ions derived from leaching, or solvent extraction is a significant contributor to the global copper commodity supply. The process of electrolysis for copper was first developed in the late 19th century and despite numerous advancements in technology the principles and basic equipment remain the same. The first part of this paper deals with the theoretical requirements and fundamental equations and principles that govern copper electrowinning. The second part discusses the practical requirements for designing a copper electrowinning plant. Electrowinning, also called electroextraction, is the electrodeposition of metals from their ores that have been put in solution via a process commonly referred to as leaching. In electrowinning, a current is passed from an inert anode through a liquid leach solution containing the metal so that the metal is extracted as it is deposited in an electroplating process.