Classification Detail

International Standard Classification of Occupations 08 (ISCO-08)

Basic Bibliographic Information

To Be Determined
International Standard Classification of Occupations: ISCO-08 / International Labour Office, - Geneva: ILO, 2012 ISBN 978-92-2-125952-7 (print) ISBN 978-92-2-125953-7 (web pdf)
International Labour Organization
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Year Adopted:
Year Published:
Available Languages (besides English):
Français, Español, العربية, Pусский Details...
Classification internationale type des professions 08 (CITP-08)
Clasificación intenacional uniforme de ocupaciones 08 (CIUO-08)
التصنيف الدولي الموحد للمهن لعام
Международная стандартная классификация занятий 08 (МСКЗ-08)
Fully available in all of the languages above

Purpose of the Classification

Statistical Domains:
1.2 Labour
To facilitate international communication about occupations by providing statisticians with a framework to make internationally comparable occupational data available, and by allowing international occupational data to be produced in a form that can be useful for research as well as for specific decision-making and action-oriented activities, such as those connected with international migration or job placement. In particular it provides: a) a contemporary and relevant basis for the international reporting, comparison and exchange of statistical and administrative information about occupations; b) a useful model for the development of national and regional classifications of occupations; and c) a system that can be used directly in countries that have not developed their own national classifications.
Main Applications:
- To produce statistics from censuses, household surveys, employer surveys and administrative sources on job seekers and job vacancies, numbers of places and enrolments in training programmes, migrant and expatriate labour employment numbers, wages, and hours worked. - Input to statistics on the socio-economic status of households ISCO and national classifications based on it or also used in admnistrative and policy-related activities such as: • matching job seekers with job vacancies • educational planning • management of employment related international migration, including the granting of work permits
Main Users:
Ministries of labour, immigration, education and training, national employment observatories, public and private employment services, social and labour market researchers.


All jobs and work activities in the world, including jobs in employment for pay or profit and work activities in other forms of work, including own-use production, volunteer work and unpaid trainee work. When the classification was developed the focus was primarily on jobs.
Concept Being Classified:
Statistical Units:
Jobs, work activities, persons, job vacancies. A person may be associated with an occupation through the main job currently held, a second job, or a job previously held, or a specific work activity. Job or work activity is a set of tasks and duties performed, or meant to be performed, by one person for a single economic unit.The term 'job' is used with respect to employment for pay or profit. The term 'work activity' is used to refer to the same concept - For a full expalnation see paragraph 12(b) of the Resolution concerning statistics of work, emplyoment and labour underutiliaztion adopted by the 19th International Conference of Labour Statisticians (2013):
Main Principles:
An occupation is defined a set of jobs (or work activties) whose main tasks and duties are characterised by a high degree of similarity. Occupations are arranged into unit groups at the most detailed level of the classification hierarchy based on the similarity of skills required for competent performance of the tasks and duties. Unit groups are in turn arranged into minor groups, minor groups into sub-major groups, and sub-major groups into major groups based on the concept of skill level and on successively broader applications of the concept of skill specialization. Skill is defined as the ability to carry out the tasks and duties of a given job. Skill level is defined as a function of the complexity and range of tasks and duties to be performed in an occupation. Skill level is measured operationally by considering one or more of: * the nature of the work performed in an occupation in relation to the characteristic tasks and duties defined for each ISCO-08 skill level; * the level of formal education defined in terms of the International Standard Classification of Education (ISCED-97) (UNESCO, 1997) required for competent performance of the tasks and duties involved; and * the amount of informal on-the-job training and/or previous experience in a related occupation required for competent performance of these tasks and duties. Skill specialization is considered in terms of four concepts: * the field of knowledge required; * the tools and machinery used; * the materials worked on or with; and * the kinds of goods and services produced.

Classification Structure

Definition of Structure:
Level Name:
Code Format:
Number of Items:
Level 1
Major Group
10 items
Level 2
Sub-major Group
43 items
Level 3
MInor Group
130 items
Level 4
Unit Group
436 items
Criteria for Definition of Levels:
The concept of skill level is applied mainly at the top (major group) level of the classification, giving more emphasis to the first of these operational measures, the nature of the work performed, than to the formal and informal education and training requirements. Four broad skill levels are defined. As a result, eight of the ten major groups in ISCO-08 contain occupations only at one of four skill levels. For example, ISCO Major Group 2: Professionals includes only occupations at the highest ISCO skill level, Skill Level 4. All groups below the major group level contain occupations at only one skill level. Within each major group, occupations are arranged into unit groups, minor groups and sub-major groups, primarily on the basis of aspects of skill specialization. In the case of ISCO-08 Major Group 1: Managers, and Major Group 0: Armed Forces Occupations, the concept of skill level is applied primarily at the second hierarchical level.

Revision Information

Chronology of revisions/versions of the classification:
Year Adopted:
Title or Version Number:
Official Adopting Entity:
International Conference of Labour Statisticians
Coordinating Entity:
International Labour Organization
Next Review:
Reason for Latest Revision:
At the request of the 17th ICLS in 2003 to make improvement in light of eperience gained in using ISCO-88 based classifications, and as a consequence of developments in the world of work. The timing reflected the request of the 34th session of the Statistical Commission of the United Nations that the work to update ISCO-88 not later than the end of 2007 for the results to be taken into account in national preparations for the 2010 round of population censuses.
Major Changes:
The conceptual model used to guide the development of ISCO-08 was no tfundamentally changed from that used in ISCO-88. There are, however, significant differences in the treatment of some occupational groups. These differences reflect the need to address concerns about specific difficulties experienced in the use of ISCO-88, as well as the need to reflect occupational change in the 20-year period following its development. In addition, there were some changes in the way the ISCO conceptual model was applied to the design of the classification. Most notably, the nature of the work performed was given more emphasis than formal education and training requirements in determining the skill level of an occupation. The result of these changes was a modest increase in detail at each level of the classification except at the top level. The 10 major groups at the top level of the ISCO-08 are conceptually the same as those defined in ISCO-88. Since some groups of occupations were moved from one major group to another, however, there is a significant break in series for data classified at the major group level. Some of the more significant changes are summarized below. - The sections of the classification dealing with managerial occupations were reorganized so as to overcome problems experienced by users of ISCO-88. - Some additional unit groups and one new minor group were created for selected supervisory occupations, in areas where supervisors commonly perform significantly different tasks from the workers they supervise. - Occupations associated with information and communication technology were updated and expanded, allowing for the identification of professional and associate professional occupations in this field as sub-major groups. - ISCO-88 included parallel groups appearing in different major groups to cater for cases where the education and training requirements for a particular occupational group differed between countries because of differences in responsibilities and degree of supervision. Parallel groups do not appear in ISCO-08 when the tasks performed are essentially the same. - Occupations concerned with the provision of health services were expanded, in order to provide sufficient detail to allow ISCO-08 to be used as the basis for the international reporting of data on the health workforce. These occupations were grouped together, where possible, to provide two sub-major groups and a separate minor group devoted to occupations in health services. - The section of the classification dealing with office clerks was reorganized to reflect the increasing impact of information and communications technology and to provide more meaningful detail for occupations in which large numbers of women are employed. - The aggregate groups for sales and service workers were reorganized, including the provision of new sub-major groups for personal services workers, personal care workers and protective services workers. - More detailed categories and greater clarity are provided for some occupational groups involved in agriculture. - More detailed categories are provided for occupations involved in the provision of information and services to clients, including those related to tourism. - The groups for plant and machine operators were restructured and reorganized in response to concerns that this part of ISCO-88 was excessively detailed and out-of-date in some areas. - The coverage and visibility of occupations that are significant in informal employment were improved, leading to an associated increase in the number of sub-major groups in ISCO-08 Major Group 9: Elementary Occupations, compared to ISCO-88.

Supporting Documents

Coding Index Available:
Available Formats:
PDF, TXT, Excel
Correspondence with Previous Versions:
Correspondence Table:
Training Materials and Other Documents:
training materials are available on request to

Contact Information

Agency / Office:
ILO Department of Statistics
Department of Statistics
+41 22 799 8631
+41 22 799 6957
4 route des Morillons, CH-1211, Genève 22, Switzerland


The PDF publication of ISCO 08 is available at