This paper considers a range of topics concerned with the statistical application of an occupational classification, focusing in particular upon the use of the international standard, ISCO-88. Following a brief presentation of the conceptual basis of ISCO-88 and on methods of collecting and coding occupational information, evidence is presented on the reliability and validity of occupationally classified data. The paper reviews progress on the implementation of ISCO-88 on a global basis and presents an assessment of the likely comparability between countries of occupational data based upon ISCO-88.

From the evidence available it appears that ISCO-88 has successfully superseded ISCO-68 and, in many countries, has become the model for a new national classification even where a national classification of occupations previously existed.

However, occupational classification remains a difficult process, subject to a fairly low level of reliability. In addition to problems of reliability ...