Closed landfill sites invariably have physical conditions that are not immediately compatible with redevelopment options, even if they are not contaminated. This is for both "hard" and "soft" uses. Such sites represent a considerable proportion of potentially contaminated sites, and they can be brought back into beneficial use by judicious engineering and environmental control measures. Suitability will depend on factors such as age, depth and nature of wastes, in addition to the site's environmental setting and the conventional land-use planning aspects of redevelopment. Remedial engineering for closed landfill sites explores the selection of remedial options that can supplement the measures needed to meet the site owner's statutory environmental obligations.