A method of environmental classification has been applied twice to surveys of the whole of England, Scotland and Wales (the United Kingdom). Such experience is now being extended to the European continent. The paper draws on the unpublished working-papers of the relevant scientists and institutions in reconstructing both the motives and circumstances in which a methodology was developed in the UK for the assessment of the ecological resources of the wider countryside. The principles of strategic classification and subsequent sampling from defined strata were initially devised for broadleaved woodland, and first tested at a regional level. They drew on classical regression theory, with the environmental classification being the independent, and the vegetation or habitat the dependent, variable. The approach was linked to the development of efficient algorithms for analysis and classification, and more recently remote sensing and geographical information systems. Successive Countryside Surveys of the UK, carried out since 1978, have provided an objective measurement of the decline in the quality of vegetation and habitats. Such a statistically robust approach can be used to measure the rates of vegetation and habitat change at the strategic European level, and as an aid to devising appropriate rural-resources policies.