Three - sector theory - wikipedia Three - sector theory This article includes a list of references, related reading or external links, but its sources remain unclear because it lacks inline citations. Please help to improve this article by introducing more precise citations. ( August 2008 ) Economic sectors Three - sector theory Primary sector : raw materials Secondary sector : manufacturing Tertiary sector : services Additional sectors Quaternary sector : information services Quinary sector : human services Theorists AGB Fisher Colin Clark Jean Fourastié Sectors by ownership Business sector Private sector Public sector Voluntary sector Industrial output in 2005 Service output in 2005 The three - sector theory is an economic theory which divides economies into three sectors of activity : extraction of raw materials ( primary ), manufacturing ( secondary ), and services ( tertiary ). It was developed by Allan Fisher, Colin Clark and Jean Fourastié. According to the theory, the main focus of an economy 's activity shifts from the primary, through the secondary and finally to the tertiary sector. Fourastié saw the process as essentially positive, and in The Great Hope of the Twentieth Century he writes of the increase in quality of life, social security, blossoming of education and culture, higher level of qualifications, humanisation of work, and avoidance of unemployment. Countries with a low per capita income are in an early state of development ; the main part of their national income is achieved through production in the primary sector. Countries in a more advanced state of development, with a medium national income, generate their income mostly in the secondary sector. In highly developed countries with a high income, the tertiary sector dominates the total output of the economy. Contents 1 Structural transformation according to Fourastié 1.1 First phase : Traditional civilizations 1.2 Second phase : Transitional period 1.3 Third phase : Tertiary civilization 2 See also 3 Further reading Structural transformation according to Fourastié Three sectors according to Fourastié Clark 's sector model This figure illustrates the percentages of a country 's economy made up by different sector. The figure illustrates that countries with higher levels of socio - economic development tend to have less of their economy made up of primary and secondary sectors and more emphasis in tertiary sectors. The less developed countries exhibit the inverse pattern. The distribution of the workforce among the three sectors progresses through different stages as follows, according to Fourastié : First phase : Traditional civilizations Workforce quotas : Primary sector : 65 % Secondary sector : 20 % Tertiary sector : 15 % This phase represents a society which is scientifically not yet very developed, with a negligible use of machinery. The state of development corresponds to that of European countries in the early Middle Ages, or that of a modern - day developing country. Second phase : transitional period Workforce quotas : Primary sector : 40 % Secondary sector : 40 % Tertiary sector : 20 % More machinery is deployed in the primary sector, which reduces the number of workers needed. As a result, the demand for machinery production in the secondary sector increases. The transitional way or phase begins with an event which can be identified with the industrialisation : far - reaching mechanisation ( and therefore automation ) of manufacture, such as the use of conveyor belts. The tertiary sector begins to develop, as do the financial sector and the power of the state. Third phase : tertiary civilization Workforce quotas : Primary sector : 10 % Secondary sector : 20 % Tertiary sector : 70 % The primary and secondary sectors are increasingly dominated by automation, and the demand for workforce numbers falls in these sectors. It is replaced by the growing demands of the tertiary sector. The situation now corresponds to modern - day industrial societies and the society of the future, the service or post-industrial society. Today the tertiary sector has grown to such an enormous size that it is sometimes further divided into an information - based quaternary sector, and even a quinary sector based on human services. See also Colin Clark ( economist ) Jean Fourastié Primary sector of the economy Secondary sector of the economy Tertiary sector of the economy Quaternary sector of the economy Information Revolution De-industrialization crisis Private sector Further reading Bernhard Schäfers : Sozialstruktur und sozialer Wandel in Deutschland. ( `` Social Structure and Social Change in Germany '' ) Lucius und Lucius, Stuttgart 7th edition 2002 Clark, Colin ( 1940 ) Conditions of Economic Progress Fisher, Allan GB. `` Production, primary, secondary and tertiary. '' Economic Record 15.1 ( 1939 ) : 24 - 38 Rainer Geißler : Entwicklung zur Dienstleistungsgesellschaft. In : Informationen zur politischen Bildung. Nr. 269 : Sozialer Wandel in Deutschland, 2000, p. 19f. Jean Fourastié : Die große Hoffnung des 20. Jahrhunderts. ( `` The Great Hope of the 20th Century '' ) Köln - Deutz 1954 Hans Joachim Pohl : Kritik der Drei - Sektoren - Theorie. ( `` Criticism of the Three Sector Theory '' ) In : Mitteilungen aus der Arbeitsmarkt - und Berufsforschung. Issue 4 / Year 03 / 1970, p. 313 - 325 Stefan Nährlich : Dritter Sektor : `` Organisationen zwischen Markt und Staat. '' ( `` Third Sector : Organizations Between Market and State '' ). From `` Theorie der Bürgergesellschaft '' des Rundbriefes Aktive Bürgerschaft ( `` Theory of the Civil Society '' of the newsletter `` Active Civil Society '' ) 4 / 2003 Uwe Staroske : Die Drei - Sektoren - Hypothese : Darstellung und kritische Würdigung aus heutiger Sicht ( `` The Three - Sector - Hypothesis : Presentation and Critical Appraisal from a Contemporary View '' ). Roderer Verlag, Regensburg 1995 Retrieved from `` https://en.wikipedia.org/w/index.php?title=Three-sector_theory&oldid=827380007 '' Categories : Economic theories Economic sectors Hidden categories : Articles lacking in - text citations from August 2008 All articles lacking in - text citations All articles with unsourced statements Articles with unsourced statements from October 2015 Talk Contents About Wikipedia Български Català Dansk Deutsch Español Euskara हिन्दी Italiano עברית Português Русский Simple English Suomi Українська 中文 6 more Edit links This page was last edited on 24 February 2018, at 11 : 17. Text is available under the Creative Commons Attribution - ShareAlike License ; additional terms may apply. By using this site, you agree to the Terms of Use and Privacy Policy. Wikipedia ® is a registered trademark of the Wikimedia Foundation, Inc., a non-profit organization. About Wikipedia

Question: what are primary secondary and tertiary sectors of economy
Answer: extraction of raw materials (primary)