Organisation for Economic Co-operation and Development in the context of "Circular flow of income"

This is a list of cities and towns in Albania categorised by municipality, county and population, according to the criteria used by the Institute of Statistics (INSTAT). As of 2014, there were 74 cities classified as urban areas and 2,972 villages as rural areas in Albania. The legislation of Albania provides no official classification on the criteria of how to define a city or urban area. Furthermore, according to the methodology for cities conducted by the Organisation for Economic Co-operation and Development (OECD), five areas, including Tirana, Durrës, Elbasan, Shkodër and Vlorë, can be classified as urban audit cities.

Throughout most of its history, Istanbul has ranked among the largest cities in the world. By 500 CE, Constantinople had somewhere between 400,000 and 500,000 people, edging out its predecessor, Rome, for world's largest city. Constantinople jostled with other major historical cities, such as Baghdad, Chang'an, Kaifeng and Merv for the position of world's most populous city until the 12th century. It never returned to being the world's largest, but remained Europe's largest city from 1500 to 1750, when it was surpassed by London.

The Turkish Statistical Institute estimates that the population of Istanbul Metropolitan Municipality was 15,701,602 at the end of 2024, hosting 18 percent of the country's population. Then about 97–98% of the inhabitants of the metropolitan municipality were within city limits, up from 89% in 2007 and 61% in 1980. 64.9% of the residents live on the European side and 35.1% on the Asian side. While the city ranks as the world's 5th-largest city proper, it drops to the 24th place as an urban area and to the 18th place as a metro area because the city limits are roughly equivalent to the agglomeration. Today, it forms one of the largest urban agglomerations in Europe, alongside Moscow. The city's annual population growth of 3.45 percent ranks as the highest among the seventy-eight largest metropolises in the Organisation for Economic Co-operation and Development. The high population growth mirrors an urbanization trend across the country, as the second and third fastest-growing OECD metropolises are the Turkish cities of İzmir and Ankara.

Official statistics are statistics published by government agencies or other public bodies such as international organizations as a public good. They provide quantitative or qualitative information on all major areas of citizens' lives, such as economic and social development, living conditions, health, education, and the environment.

During the 15th and 16th centuries, statistics were a method for counting and listing populations and State resources. The term statistics comes from the Neo-Latin statisticum collegium (council of state) and refers to science of the state. According to the Organisation for Economic Co-operation and Development (OECD), official statistics are statistics disseminated by the national statistical system, excepting those that are explicitly not to be official".

The Global Financial Centres Index (GFCI) ranks the competitiveness of financial centres based on over 29,000 assessments from an online questionnaire and over 100 indices from organisations such as the World Bank, the Organisation for Economic Co-operation and Development (OECD), and the Economist Intelligence Unit. It was first published in March 2007. It has been jointly published twice per year by the London-based think tank Z/Yen and the China Development Institute since 2015. It is widely quoted as a top source for ranking financial centres.

Non-formal learning includes various structured learning situations which do not either have the level of curriculum, institutionalization, accreditation or certification associated with 'formal learning', but have more structure than that associated with 'informal learning', which typically take place naturally and spontaneously as part of other activities. These form the three styles of learning recognised and supported by the OECD.

Examples of non-formal learning include swimming sessions for toddlers, community-based sports programs, and programs developed by organisations such as the Boy Scouts, the Girl Guides, community or non-credit adult education courses, sports or fitness programs, professional conference style seminars, and continuing professional development. The learner's objectives may be to increase skills and knowledge, as well as to experience the emotional rewards associated with increased love for a subject or increased passion for learning.

The arm's length principle (ALP) is the condition or the fact that the parties of a transaction are independent and on an equal footing. Such a transaction is known as an "arm's-length transaction". It is used specifically in contract law to arrange an agreement that will stand up to legal scrutiny, even though the parties may have shared interests (e.g., employer-employee) or are too closely related to be seen as completely independent (e.g., the parties have familial ties).

An arm's length relationship is distinguished from a fiduciary relationship, where the parties are not on an equal footing, but rather, power and information asymmetries exist. It is also one of the key elements in international taxation as it allows an adequate allocation of profit taxation rights among countries that conclude double tax conventions, through transfer pricing, among each other. Transfer pricing and the arm's length principle were one of the focal points of the base erosion and profit shifting (BEPS) model developed by the OECD and endorsed by the G20.

Influence peddling, also called traffic of influence or trading in influence, is the practice of using one's influence in government or connections with authorities to obtain favours or preferential treatment for another, usually in return for payment. Influence peddling per se is not necessarily illegal, as the Organisation for Economic Co-operation and Development (OECD) has often used the modified term "undue influence peddling" to refer to illegal acts of lobbying; however, influence peddling is typically associated with corruption and may therefore delegitimise democratic politics with the general public. It is punishable as a crime in Argentina, Belgium, Bulgaria, Brazil, France, Hungary, Italy, Lithuania, Mexico, Portugal, Romania, Spain, and the United Kingdom.

In environmental law, the polluter pays principle is enacted to make the party responsible for producing pollution responsible for paying for the damage done to the natural environment. This principle has also been used to put the costs of pollution prevention on the polluter.  It is regarded as a regional custom because of the strong support it has received in most Organisation for Economic Co-operation and Development (OECD) and European Union countries, and has a strong scientific basis in economics. It is a fundamental principle in US environmental law.