Re-processing of "old" residue tailings has proved to be a profitable business for several operations, usually when incorporated into an existing facility to supplement declining ore arisings. These resources often prove to be a source of "cheap gold" since the high mining and feed preparation costs have already been incurred and only "variable" treatment costs are incurred in addition to the relatively low reclamation costs. Advances in processing technology, together with a degree of gold release through ageing of the ore over many years, often provide gold recovery in the range 50-60% (headgrade around 0.4-0.5 g/t), which is sufficient to cover the low processing costs and make a positive contribution to the profitability of an operation. Additional benefits such as releasing land for urban development or reducing environmental liabilities may also flow from this type of exercise. The paper covers key practical aspects of developing and implementing a residue re-treatment project beginning with evaluation of the resource, through the implementation phase and into final closure. (C) 2005 Published by Elsevier Ltd.