Most primary metal production includes some hydrometallurgical processing to obtain a finished metal product. Some metals, such as copper and gold, can be processed from crushed ore or concentrated minerals to purified metal using hydrometallurgy. The basic processing steps include extraction, concentration/purification, and recovery. In this chapter, hydrometallurgical processing will be discussed based on hydrometallurgical fundamentals and their application to copper, gold, and zinc processing. The fundamental concepts and the processing methods discussed in this chapter are widely applicable to a variety of metals.