In-place leaching is being actively utilized to extract uranium, copper, and evaporites from low-grade and difficult-to-mine ores. This report discusses in-place leaching technology, its advantages and disadvantages, and gives an overview of past, current, and envisioned in-place leaching operations in the United States. Application of in-place leaching to uranium ores has been particularly successful. The sandstone ores are contained above and below by impermeable shales, and the uranium ore minerals are easily leached with oxidizing acid or base solutions. Copper is recovered from subgrade rock by dump or inplace leaching with acidified ferric sulfate solutions. The leaching solution migrates down through the rock and dissolves copper. The solution is collected from the base of the dumps, and copper is recovered by solvent extraction- electrowinning or by cementation on detinned steel cans. Solution mining of evaporites is being conducted commercially for the extraction of sodium chloride and potassium chloride.