Not everything that can be counted counts and not everything that counts can be counted' a famous quote by Cameron (1963) which is very insightful and interesting. It explains what many in the 21st century are trying to do and reminds us that there are many things that have more to them than we count them for in our books. GDP essentially measures and counts all of an economy's economic output/input in terms of money. In this essay I will address key terms and explain how GDP is in some ways a good measure, but does not fully reflect the reality of wealth and well-being. I will then conclude with my opinion and explain how new measurement tools have come into force and become more important. Gross Domestic Product was a theory introduced by President Roosevelt before the 1930s as a measure for the entire economy. . But it was only during the Second World War that GDP became an important measure for Britain to gauge how well it could cope with the war. Initially, GDP was used as an emergency tool to measure the wealth of the economy. Today it has become the key tool for measuring and comparing the growth of economies around the world. GDP measures the value of economic activity within a country. More precisely, GDP is the sum of the prices of all final goods and services produced in the country during a period of time, usually a year. It measures the legal activities performed by businesses/individuals and places a monetary value on their work. GDP, which was originally GNP (gross national product), was used by creator Simon Kuznets and also by John Maynard Keynes as a tool to aid in political decisions and war planning. GDP= C+I+G+(XM). This formula is now...... half of the document...... doi: 10.1080/09538259.2013.807671 [11/20/13].• Lauderdale, J. nd Remarks on the revision of his investigation into the nature and origin of public wealth. Edinburgh: Printed by D. Willison, 1804.• Malthus, T. 1820. Principles of political economy considered with a view to their practical application. London: John Murray, Albermarlestreet.• Michalos, A. 2010. What did Stiglitz, Sen and Fitoussi get right and what did they get wrong? Social Indicators Research, 102(1), pp. 117-129. Available from: doi: 10.1007/s11205-010-9734-0 [11/25/13].• Smith, A. 1910. The Wealth of Nations. London: JM Dent.• Stiglitz, J., Sen, A. and Fitoussi, J. 2009. Report of the Commission on the Measurement of Economic Performance and Social Progress. [report] Paris: Commission. [Online] Available at: http://www.stiglitz-sen-fitoussi.fr/documents/rapport_anglais.pdf [20/11/13]