In situ leach (ISL) mining of uranium involves injecting mild acidic or alkaline chemicals through surface boreholes into permeable, uranium-bearing sandstones. The chemicals dissolve the uranium, and the uranium-bearing solutions are pumped to the surface through a second set of boreholes. ISL mining of uranium totalled 6410 tonnes of uranium in 2002, and accounted for 18% of worldwide uranium production. Seven countries reported ISL production in 2002, and other countries are considering the potential for developing an ISL capability, as ISL has economic and environmental advantages for producing uranium from carefully selected deposits. This publication contains 26 papers on various aspects of ISL mining including the geology of ISL-amenable sandstone deposits, case histories of ISL production using leaching solutions of varying chemistry and finally post-mining rehabilitation of ISL projects. The papers were presented at a meeting held in Beijing, China, in 2002, attended by 59 scientists from 18 countries and one international organization (OECD/NEA). Attendees at the meeting also toured one of China’s ISL operations, a description of which is included in this publication.