Heap leaching technology is moving forward rapidly as it satisfies most techno-economic considerations and provides several benefits such as low cost, cleaner environment and product, flexibility, and diversified process conditions. Factors such as proper feed preparation, adequate mineralogical analysis, implementation of eco-comminution, and the precise use of characterization tools should be undertaken in order to provide for a successful heap leach process. In view of the important role of comminution and agglomeration in heap leaching systems, both of which have to do with particle size distribution (PSD), improved characterization methods have become of significance in the design and operation of heap leaching systems. An increase in fundamental understanding using advanced characterization tools such as X-ray computed tomography (CT) will make heap leach technology even more adaptable to ever-increasing complex ores in the foreseeable future. High pressure grinding rolls (HPGRs) may become more popular in heap leach operations since they offer several advantages over conventional crushing technologies such as lower energy consumption and increased particle damage. The potential applications of X-ray CT to heap leaching technology and future directions are reported. (C) 2012 Elsevier Ltd. All rights reserved.