International Standard Classification of Occupations (ISCO)

Classifications of occupations are used in national contexts for the collection and dissemination of statistics from sources such as population censuses, labour force surveys and other household surveys, employer surveys and other sources.  They are also used by governments and companies in activities such as matching jobseekers with job vacancies, educational planning, reporting of industrial accidents, administration of workers’ compensation, and the management of employment-related migration.

The International Classification of Occupations (ISCO) seeks 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.

The current version, known as ISCO-08, was published in 2008 and is the fourth iteration, following ISCO-58, ISCO-68 and ISCO-88.  Only the latest two versions, ISCO-08 and ISCO-88, are presented below, along with the corresponding skill levels.

Definitions

A job is defined in ISCO-08 as “a set of tasks and duties performed, or meant to be performed, by one person, including for an employer or in self employment”.

Occupation refers to the kind of work performed in a job. The concept of occupation is defined as a “set of jobs whose main tasks and duties are characterized by a high degree of similarity”.  A person may be associated with an occupation through the main job currently held, a second job, a future job or a job previously held. 

Skill is defined as the ability to carry out the tasks and duties of a given job. For the purposes of ISCO-08, two dimensions of skill are used to arrange occupations into groups.  These are skill level and skill specialization.

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.

ISCO-88

Major Group1

Legislators, Senior Officials and Managers

11 – Legislators and Senior Officials

12 – Corporate Managers (This group is intended to include persons who – as directors, chief executives or department managers – manage enterprises or organisations, or departments, requiring a total of three or more managers.)

13 – General Managers (This group is intended to include persons who manage enterprises, or in some cases organisations, on their own behalf, or on behalf of the proprietor, with some non-managerial help and the assistance of no more than one other manager who should also be classified in this sub- major group as, in most cases, the tasks will be broader than those of a specialised manager in a larger enterprise or organisation. Non-managerial staff should be classified according to their specific tasks.

Major Group 2

Professionals

21 – Physical, Mathematical and Engineering Science Professionals

22 – Life Science and Health Professionals

23 – Teaching Professionals

24 – Other Professionals

Major Group 3

Technicians and Associate Professionals

31 – Physical and Engineering Science Associate Professionals

32 – Life Science and Health Associate Professionals

33 – Teaching Associate Professionals

34 – Other Associate Professionals

Major Group 4

Clerks

41 – Office Clerks

42 – Customer Services Clerks

Major Group 5

Service Workers and Shop and Market Sales Workers

51 – Personal and Protective Services Workers

52 – Models, Salespersons and Demonstrators

Major Group 6

Skilled Agricultural and Fishery Workers

61 – Market-Oriented Skilled Agricultural and Fishery Workers

62 – Subsistence Agricultural and Fishery Workers

Major Group 7

Craft  and Related Trades Workers

71 – Extraction and Building Trades Workers

72 – Metal, Machinery and Related Trades Workers

73 – Precision, Handicraft, Printing and Related Trades Workers

74 – Other Craft and Related Trades Workers

Major Group 8

Plant and Machine Operators and Assemblers

81 – Stationary-Plant and Related Operators

82 – Machine Operators and Assemblers

83 – Drivers and Mobile-Plant Operators

Major Group 9

Elementary Occupations

91 – Sales and Services Elementary Occupations

92 – Agricultural, Fishery and Related Labourers

93 – Labourers in Mining, Construction, Manufacturing and Transport

Major Group 0

Armed Forces

01 – Armed Forces

ISCO-08

Major Groups

1. Managers

2. Professionals

3. Technicians and Associate Professionals

4. Clerical Support Workers

5. Services and Sales Workers

6. Skilled Agricultural, Forestry and Fishery Workers

7. Craft and Related Trades Workers

8.  Plant and Machine Operators and Assemblers

9. Elementary Occupations

0. Armed Forces Occupations

Major and Sub-Major Groups

1. Managers

11 – Chief Executives, Senior Officials and Legislators

12 – Administrative and Commercial Managers

13 – Production and Specialized Services Managers

14 – Hospitality, Retail and Other Services Managers

2. Professionals

21 – Science and Engineering Professionals

22 – Health Professionals

23 – Teaching Professionals

24 – Business and Administration Professionals

25 – Information and Communications Technology Professionals

26 – Legal, Social and Cultural Professionals

3. Technicians and Associate Professionals

31 – Science and Engineering Associate Professionals

32 – Health Associate Professionals

33 – Business and Administration Associate Professionals

34 – Legal, Social, Cultural and Related Associate Professionals

35 – Information and Communications Technicians

4. Clerical Support Workers

41 – General and Keyboard Clerks

42 – Customer Services Clerks

43 – Numerical and Material Recording Clerks

44 – Other Clerical Support Workers

5. Services and Sales Workers

51 – Personal Services Workers

52 – Sales Workers

53 – Personal Care Workers

54 – Protective Services Workers

6. Skilled Agricultural, Forestry and Fishery Workers

61 – Market-oriented Skilled Agricultural Workers

62 – Market-oriented Skilled Forestry, Fishery and Hunting Workers

63 – Subsistence Farmers, Fishers, Hunters and Gatherers

7. Craft and Related Trades Workers

71 – Building and Related Trades Workers (excluding Electricians)

72 – Metal, Machinery and Related Trades Workers

73 – Handicraft and Printing Workers

74 – Electrical and Electronic Trades Workers

75 – Food Processing, Woodworking, Garment and Other Craft and Related Trades Workers

8. Plant and Machine Operators and Assemblers

81 – Stationary Plant and Machine Operators

82 – Assemblers

83 – Drivers and Mobile Plant Operators

9. Elementary Occupations

91 – Cleaners and Helpers

92 – Agricultural, Forestry and Fishery Labourers

93 – Labourers in Mining, Construction, Manufacturing and Transport

94 – Food Preparation Assistants

95 – Street and Related Sales and Services Workers

96 – Refuse Workers and Other Elementary Workers

0. Armed Forces Occupations

01 – Commissioned Armed Forces Officers

02 – Non-commissioned Armed Forces Officers

03 – Armed Forces Occupations, Other Ranks

Skill levels

Statistics by occupation are presented in ILOSTAT according to both the categories of the latest version of the ISCO available and broad skill levels, based on the following correspondence table:

Broad skill levelISCO-08ISCO-88
Skill levels 3 and 4 (high)1. Managers1. Legislators, senior officials and managers
2. Professionals2. Professionals
3. Technicians and associate professionals3. Technicians and associate professionals
Skill level 2 (medium)4. Clerical support workers4. Clerks
5. Service and sales workers 5. Service workers and shop and market sales workers
6. Skilled agricultural, forestry and fishery workers6. Skilled agricultural and fishery workers
7. Craft and related trades workers7. Craft and related trades workers
8. Plant and machine operators, and assemblers8. Plant and machine operators and assemblers
Skill level 1 (low)9. Elementary occupations9. Elementary occupations
Armed forces0. Armed forces occupations 0. Armed forces
Not elsewhere classifiedX. Not elsewhere classified X. Not elsewhere classified