1220.0 - Australian Standard Classification of Occupations (ASCO) Second Edition, 1997  
ARCHIVED ISSUE Released at 11:30 AM (CANBERRA TIME) 31/07/1997   
   Page tools: Print Print Page  




The Australian Standard Classification of Occupations (ASCO), Second Edition is the product of a review program undertaken jointly by a project team from the Australian Bureau of Statistics (ABS) and the Department of Employment, Education, Training and Youth Affairs (DEETYA) for use in the collection, publication and analysis of statistics.

Major government agencies such as the Commonwealth Employment Service, the Department of Immigration and Multicultural Affairs and Comcare have incorporated ASCO into their reporting systems.

In addition, ASCO is the specified standard for the reporting of workplace accidents under the revised Regulations of the Occupational Health and Safety (Commonwealth Employment) Act 1991. Other organisations in both the public and private sectors use ASCO to store and organise occupation-related information for such purposes as policy development and review, human resource management, labour market analysis and social research.

ASCO is used in all ABS censuses and surveys where occupation data are collected, including the 1986, 1991 and 1996 Censuses of Population and Housing, the Labour Force Survey, the Survey of Employee Earnings and Hours, the Survey of Employment and Unemployment Patterns and a wide range of household surveys on particular social and labour market topics. ASCO is also used in a number of ABS administrative by-product collections such as births, deaths, marriages and divorces.

These introductory chapters provide an overview of the conceptual basis and structure of ASCO Second Edition, describe some of the principal differences between the First and Second Editions of ASCO, explain the ASCO Second Edition Code Structure and outline the format of the ASCO Second Edition occupation and group definitions.


Widespread industry and award restructuring, technological change and competency-based approaches to career entry and progression have brought about significant changes in the Australian labour market since ASCO First Edition was released in 1986.

To ensure that occupation statistics classified to ASCO are relevant and responsive to the current and evolving needs of the community, the ABS and DEETYA commenced a review of the classification in 1992. This review encompassed both the structural and the definitional content of the classification.

The terms of reference for the review were as follows:
  • provide a framework for analysing Australia's occupation labour market over the ten years from 1996 to 2005;
  • take account of major new developments across employment, education and training, particularly award restructuring and competency-based approaches to career entry and progression (as distinct from approaches based on time served or qualifications gained);
  • take account of change and development within particular occupations, due to technological changes and industry restructuring;
  • produce sound statistics which can be compared with those produced from the ASCO First Edition and the International Standard Classification of Occupations (ISCO); and
  • develop a maintenance program, so that less work should be involved in the movement towards a third edition for the Census of 2006.

The classification structure of the Second Edition was finalised in mid-1996 with details provided in Information Paper: ASCO-Australian Standard Classification of Occupations (Cat. no. 1221.0) released in July 1996.

The Second Edition has been introduced to ABS collections from mid-1996 onwards, starting with the May 1996 Survey of Employee Earnings and Hours, the August 1996 Labour Force Survey, and the 1996 Census of Population and Housing. Occupation data from the Census and from the Survey of Employee Earnings and Hours were dual coded to both the First and Second Editions of ASCO, to provide a link between the two versions of the classification.

Occupation data collected in the 1996 second wave of the longitudinal Survey of Employment and Unemployment Patterns were coded to ASCO Second Edition. Data from the 1995 first wave of this survey were originally coded to ASCO First Edition and have been re-coded to the Second Edition.


Concordances between occupations in the two editions are included in this document at Appendixes A1, A2, B1 and B2. These show the links from ASCO Second Edition to ASCO First Edition and from First Edition to Second Edition. The concordances indicate where a one-to-one relationship exists between occupations in the First and Second Editions and where a partial relationship exists (indicated by the letter p).

These concordances provide a conceptual link between occupations in the two editions of ASCO. A detailed link file indicating proportional relationships (as well as one-to-one links) will be produced following the completion of processing of data from the 1996 Census of Population and Housing.


This publication is a reference document intended to provide a detailed account of the content and structure of the ASCO Second Edition and to assist the interpretation of statistics classified to it. It is not intended as a means of assigning information about particular jobs to ASCO Second Edition classes.

Assigning ASCO codes to occupation or job descriptions requires the use of a rule-based system to ensure that it is performed in an accurate, consistent and efficient manner. The system developed by the ABS for this purpose is referred to as the ASCO Coding System.

To consistently and reliably allocate responses from statistical collections to any level of the ASCO structure, as a minimum requirement data on occupation tasks as well as the occupation title are needed. The coding system, based on an index of responses given in ABS collections, is designed to utilise, in a structured way, the responses from up to four distinct questions: occupation title, main tasks performed, industry of employer and employer's name. Primary importance is given to the occupation title, but extensive use is made of main tasks performed in the job. Restricted use can also be made of information given in response to questions on industry and employer's name when it is collected.

This structured coding system may be implemented as a clerical procedure or through computer-assisted coding. There is no functional difference between the two forms of coding; that is, they are based on the same coding methodology, index and procedures, and are designed to yield the same results.

The review of ASCO was accompanied by the development of a Windows-based structured coding system for PCs, which enables occupation responses to be coded to either the unit group or occupation level of the classification with a high degree of accuracy and consistency. This Windows-based system will replace the ASCO Expert system (a DOS-based system) which was developed for coding to ASCO First Edition.

Users wishing to assign ASCO Second Edition codes to occupation information are advised to use the Windows-based computer-assisted coding system provided on the ASCO Australian Standard Classification of Occupations, Second Edition on CD-ROM (Cat no. 1220.0.30.001). The coding system enables occupation responses to be coded with a high degree of accuracy and consistency. The coding index (in both alphabetical and numerical order) is also provided as a rich text format (rtf) file for users requiring a hard copy of the index.


An important consideration when developing a statistical classification is the need to build in sufficient robustness to allow for long-term usage. This robustness facilitates meaningful time series analysis of data assigned to that classification. At this stage, it is anticipated that ASCO Second Edition will have a shelf life of approximately ten years, with the next major review to commence early in the twenty-first century. There will be provision, however, to make minor amendments to ASCO, such as updating occupation descriptions, where it can be illustrated that significant user requirements exist to warrant making a change.


The International Standard Classification of Occupations (ISCO) was developed by the International Labour Office in Geneva. ISCO was first issued in 1958 and revised versions were produced in 1968 and 1988. The main aims of ISCO are to provide a basis for international comparisons of occupation statistics between member countries and to provide a conceptual model for the development of national occupation classifications. The most recent edition, ISCO-88, was developed using a similar conceptual basis to that of ASCO First Edition.

At the time of its release in 1986, ASCO First Edition was significantly different from most other occupation classifications used by national and international statistical agencies. The major change from international practice at that time lay in the use of skill level and skill specialisation as criteria to structure the occupation classification. ISCO-88 also uses these criteria in the conceptual framework for the classification. Four broad skill levels are used, defined in terms of the educational categories and levels which appear in the International Standard Classification of Education, published by the United Nations Educational, Scientific and Cultural Organisation.

ISCO-88 consists of 10 major groups, 28 sub-major groups, 116 minor groups and 390 unit groups. The occupation level is not defined in ISCO-88, as it is expected that individual countries will develop this level of detail to suit national requirements. The ten major groups in ISCO-88 remain broadly similar to the nine ASCO Second Edition major groups. The most significant difference at major group level is that ISCO-88 has identified Skilled Agricultural and Fishery Workers as a separate major group (Major Group 6), whereas ASCO Second Edition includes Farmers and Farm Managers as a sub-major group in Major Group 1 Managers and Administrators, and Skilled Agricultural and Horticultural Workers as a sub-major group in Major Group 4 Tradespersons and Related Workers.

ISCO-88 also includes a separate Major Group 0, for the Armed Forces. In ASCO Second Edition, jobs held by members of the Armed Forces are classified together with their civilian equivalents where these exist and to a number of other specific occupations.

In common with ISCO-88, ASCO Second Edition now incorporates the sub-major group as a level of aggregation between the major and minor groups.


In 1995, Statistics New Zealand released the New Zealand Standard Classification of Occupations (NZSCO), as the result of a minor review of the previous NZSCO90. It is a skill-based classification which uses skill level and skill specialisation as the primary criteria for classifying occupations. NZSCO95 has nine major groups, similar to ASCO Second Edition, and has the same five levels in the classification hierarchy - major group, sub-major group, minor group, unit group and occupation.

Early in the development phase of ASCO Second Edition, consideration was given to developing a joint Australian and New Zealand classification. However, a number of practical issues precluded this development, chiefly the timing of the ASCO review in relation to NZSCO and the need to have ASCO Second Edition ready for use in the 1996 Census.

Previous PageNext Page