Technology Assessment (TA) and Environmental Impact Assessment (EIA) have developed through separate paths and traditions. Of the two EIA has reached a degree of formalism and political acceptance, through a European Directive and its earlier equivalent (NEPA) in the USA. The extent of the separation between the two modes of enquiry seems unnecessary and artificial, since it is difficult to separate the purposes of the two activities. The similarities and interdependence of TA and EIA is outlined and the essential difference between the two is also discussed. Copyright © 1996 Inderscience Enterprises Ltd.