BRITISH PORTS POLICIES SINCE 1945.

privatisation. It may be argued that many of these changes, and their results, have stemmed from adopting ideas developed in other contexts without appreciating the special charac teristics of seaports: that is, from a failure to understand the basic principles of the subject. It must, of course, be admitted that academic studies of seaport economics have also been lacking, notably in employing the concept of economic rent and the related problems of its distribution. The most sensible economic objective for national seaport policies (Goss, 1990a) is to aim to maximise the sum of the producers' surpluses on the exports, and of consumers' surpluses on the imports, passing through them, subject to the constraint of covering the marginal opportunity costs of the resources involved. However, a number of other factors may intervene. Other economic objectives may be specified, such as "maximising jobs in the locality", even though this is likely to prove difficult, and no rational level of assistance can be specified.1 With or without formal investment appraisals, over-optimistic trade forecasts may be adopted.2 Non-economic objectives may appear, as with Palmerston's