The rectangular area of North Africa, the Middle East and Asia between 10 degrees north and 40 degrees north latitude. The 10/40 Window is often called "The Resistant Belt" and includes the majority of the world's Muslims, Hindus, and Buddhists. An estimated 5.21 billion individuals reside in approximately 8,873 distinct people groups in the 10/40 Window. The 10/40 Window is home to some of the largest unreached people groups in the world such as the Shaikh, Yadava, Turks, Moroccan Arabs, Pashtun, Jat and Burmese. The 10/40 Window has several important ... read more

Source: AD2000 and Beyond Movement

Affinity Blocs

All people groups, who either live in a particular region or have similar cultural roots. Peoples are broadly grouped into 16 blocs with affinities based on language, culture, religion, politics. In nearly every Bloc there are widely dissimilar and unrelated linguistic minorities, but often there is one particular culture that is dominant.

Affinity Blocs are the top level of the Ethnic Peoples tree and use the Joshua Project code PeopleID1 which is related to the Harvest Information Standards code ROP1.

Learn more:

Source: Patrick Johnstone

The rigid South Asian structure of hereditary social classes. Caste and social status are determined at birth and cannot be changed. Marriage is restricted to members of one's own caste. The caste system originally had four levels: Brahman - seers (priests, teachers), Kshatriya - administrators (military leaders, business owners), Vaisya - producers (skilled craftspersons), and Shoodra - servants (unskilled laborers). Each caste is split into countless sub-castes.

Today there are four general caste levels in South Asia:
  • Forward Castes (FC)
  • Backward Castes (BC)
  • Other Backward Castes (OBC)
  • Scheduled Castes and Tribes (SC/ST)

The word "caste" is actually a corrupted Portuguese word. The more useful term for sociological groupings is "Jati." Jati as used in South Asia is a very close fit to the definition of "people group."

Source: Omid - South Asia Researcher
Anyone who professes to be Christian. The term embraces all traditions and confessions of Christianity. It is no indicator of the degree of commitment or theological orthodoxy. This definition is based on the individual's self-confession, not his or her ecclesiology, theology or religious commitment and experience. This includes professing and affiliated adults and also their children (practicing and non-practicing) who reside in a given area or country, or who are of a particular ethno-linguistic or ethno-cultural people.

This is the broadest possible classification of Christian and includes the six ecclesiological types of Christians: Protestant, Roman Catholic, Other Catholic, Orthodox, Foreign marginal, Indigenous marginal as defined in Operation World. Professing Christian numbers include the Evangelical subset. May also include those who self-identify as followers of Jesus, but do not use the label "Christian".

Source: Operation World

"Usually written as "church" with lower case "c." A gathering of followers of Christ. Does not imply a building or specific location. A fellowship of believers committed to spiritual growth and mutual encouragement. Starting these fellowships is often called church planting." (Operation World,, 2010)

Additional definitions of church from various sources:

"God’s message fleshed out in their culture, producing vibrant churches that plant other churches, with locals leading from the beginning – that’s the goal. A group of local people who follow God and love each other will deeply impact their community in the long term." (WEC Church Planting,, 2012)

"An autonomous local congregation of baptized believers, associated by covenant in the faith and fellowship of the gospel; observing the two ordinances of Christ, governed by His laws, exercising the gifts, rights, and privileges invested in them by His Word, and seeking to extend the gospel to the ends of the earth." (IMB "Definition of a Church" 2005)

"An assembly of disciples who know and reflect their identity in Christ expressed through corporate worship and mission." (AIM International 2008)

"A group of baptized believers in the Lord Jesus Christ who meet regularly to worship, nurture one another (feed and grow one another), and fellowship (practice the one another statements of the Bible), and depart these gatherings endeavoring to obey all the commands of Christ in order to transform individuals, families, and communities." (David Watson, CPM Trainer,, 2009)

A rapid and multiplicative increase of indigenous churches planting churches within a given people group or population segment. Characteristics of a Church Planting Movement or Kingdom Movement:

Rapid: As a movement, a Church Planting Movement occurs with rapid increases in new church starts. Saturation church planting over decades and even centuries is good, but doesn’t qualify as a Church Planting Movement.

Multiplicative: This means that the increase in churches is not simply incremental growth—adding a few churches every year or so. Instead, it compounds with two churches becoming four, four churches becoming eight to 10 and so forth. Multiplicative increase is only possible when new churches are being started by the churches themselves–rather than by professional church planters or missionaries.

Indigenous: This means they are generated from within rather than from without. This is not to say that the gospel is able to spring up intuitively within a people group. The gospel always enters a people group from the outside; this is the task of the missionary. However, in a Church Planting Movement the momentum quickly becomes indigenous so that the initiative and drive of the movement comes from within the people group rather than from outsiders.

Universal Elements: Characteristics of most all Church Planting Movements.

1. Extraordinary prayer6. Lay leadership
2. Abundant Gospel sowing7. Cell or house churches
3. Intentional church planting8. Churches planting churches
4. Scriptural authority9. Rapid reproduction
5. Local leadership10. Healthy churches

Source: Church Planting Movements / David Garrison
0CPM Team in context but no purposeful CPM plan or efforts yet. Considered unengaged.
1Moving purposefully – Trying to consistently establish 1st generation of NEW indigenous believers and churches. Considered engaged.
1.1Purposeful entry (looking for person of peace / houses of peace) and reproducible evangelism activity but no results yet
1.2Have some new 1st generation believers
1.3Have some new 1st generation believers and new groups
1.4Have consistent new 1st generation believers
1.5Have consistent new 1st generation believers and new groups
1.6One or more new 1st generation churches
1.7Several new 1st generation churches
1.81st generation churches are starting new groups
1.9Close to second generation churches (1 + G2 Church)
2Focused – Some 2nd generation churches (i.e. new indigenous believers / churches have started another generation)
3Breakthrough – Consistent 2nd generation and some 3rd gen churches
4Emerging CPM – Consistent 3rd gen churches and some 4th gen churches
5CPM - consistent 4th++ generation churches in multiple streams
6Sustained CPM – Visionary, indigenous leadership leading the movement with little/no need for outsiders. Stood test of time with at least several hundred churches
7Initial CPM is now catalyzing other CPMs in other people groups or cities
Source: Church Planting Movements
A coding mechanism developed by the World Christian Database for classifying people groups. Consists of six characters with each column having a specific meaning. An example is the Tajik with culture code CNT24g.
1st letter 2nd letter 3rd letter 4-5th numbers 6th letter
geographic ethnicity
major culture area
ethnocultural family people within family

The following are the values for the first three letters in the code:

First letter Second letter Third letter
A = Australoid E = European B = Black
B = Capoid F = Afro-American G = Grey
C = Caucasian I = American Indian N = Brown
M = Mongoloid L = Latin American R = Red
N = Negroid M = Middle Eastern T = Tan
N = Indo-Iranian W = White
O = Oceanic Y = Yellow
P = Pacific
R = Arctic Mongoloid
S = Asian
U = Austro-Asiatic
Y = Early African

Source: World Christian Database

A hierachical structure classifying people groups. It is a four level tree structure with:

Ethnic Peoples Tree

Learn more:
Source: Joshua Project and Patrick Johnstone

Groupings of individuals based primarily on language spoken, but with the possibility of sub-divisions based upon dialect or cultural distinctives.

Using this method, one language group equals one or more ethnic groups. This assumes that the "understandability barrier" to the gospel message is higher than the "acceptance barrier." For the related article about how people groups are defined, click here.

The Ethno-linguistic people group model is appropriate for language-based out reaches of various kinds. It is more appropriate for church planting / discipleship than a strictly linguistic (language) group approach, because it recognizes understandability and acceptance barriers that a strictly language-based approach may not.

However the ethno-linguistic approach is less appropriate for church planting / discipleship activity when the acceptance barrier is higher than the understandability barrier. The ethno-linguistic people group model is appropriate in most of the world, outside of the South Asian countries of India, Pakistan, Bangladesh, Nepal, Bhutan and Sri Lanka, where a caste / community model may be more appropriate.

Source: Joshua Project

Followers of Christ who generally emphasize:

  • The Lord Jesus Christ as the sole source of salvation through faith in Him.
  • Personal faith and conversion with regeneration by the Holy Spirit.
  • A recognition of the inspired Word of God as the only basis for faith and living.
  • Commitment to Biblical preaching and evangelism that brings others to faith in Christ.

The noun "Evangelical" is capitalized since it represents a body of Christians with a fairly clearly defined theology (as also Orthodox and Catholic bodies, etc.). Evangelicals are here defined as:

  • All affiliated Christians (church members, their children, etc.) of denominations that are evangelical in theology as defined above.
  • The proportion of the affiliated Christians in other denominations (that are not wholly evangelical in theology) who would hold evangelical views.
  • The proportion of affiliated Christians in denominations in non-Western nations (where doctrinal positions are less well defined) that would be regarded as Evangelicals by those in the above categories.
  • This is a theological and not an experiential definition. It does not mean that all Evangelicals as defined above are actually born-again. In many nations only 10-40% of Evangelicals so defined may have had a valid conversion and also regularly attend church services. However, it does show how many people align themselves with churches where the gospel is being proclaimed.

In the United States, the term has sometimes been made equivalent to the Religious Right or a conservative voting bloc. On this website, the term is always intended in its historical and more global definition and does not have political implications.

Source: Operation World and Joshua Project

People groups with estimated Christian Adherents less than or equal to 0.1% and without clear evidence of a sufficient gospel movement adequate to impact the whole group.

Frontier people groups do not have a reported indigenous, self-sustaining church planting movement (CPM) occuring in their midst capable of reaching the whole group. Movement data is beginning to be gathered, but a comprehensive dataset is not yet available.

For additional information, see Frontier Peoples.

31 Frontier Peoples prayer guide:   PDF version      Print at Home

For listings and maps of Frontier Peoples at various population levels, click here.

Source: Joshua Project, Go31, 24:14 Initiative and Frontier Ventures

The Global Status of Evangelical Christianity (GSEC), developed by, is a model that describes the progress of the Gospel among people groups by considering:

  • The extent to which a people group is Evangelical.
  • Accessibility to the Gospel.
  • Church planting activity, whether localized or widespread, within the past 2 years.

The cooperative network of registry stewards and their combined information resources collected into the Harvest Information Standards database.

  • ROG3 = 2 letter Country Code (FIPS)
  • ROP3 = 6 digit People Code
  • ROL3 = 3 letter Language Code (Ethnologue Code)

For official Harvest Information Standards (HIS) Registry data, codes and categories, please visit the Harvest Information Standards website.

Source: Harvest Information Standards

A measure of country development generated by the United Nations. HDI indicators are standardized and ranked against other countries values to generate an index between 0 and 1. The Human Development Index is based on three indicators:

  • Life Expectancy Index: Longevity, as measured by life expectancy at birth
  • Education Level Index: Educational attainment, as measured by a combination of adult literacy (two-thirds weight) and the combined gross primary, secondary and tertiary enrollment ratio (one-third weight)
  • Gross Domestic Product: Standard of living, as measured by real GDP per capita.
Source: UN Human Development Report

"Well established, multi-generational community" within a country, as the Ethnologue uses this phrase to identify indigenous languages. Joshua Project primarily uses language-spoken to identify indigenous people groups in each country. If the language is considered to be indigenous, the people group speaking the language is usually regarded as indigenous to the country.

In many cases, it is not at all clear as to whether a people group should be considered indigenous. Joshua Project provides a "first cut" approximation of this category for each country. Users of these markings should evaluate our markings according to their own needs and priorities.

Our desire is that these indigenous / non-indigenous markings will stimulate thought as to whether indigenous people groups should be ministered to differently than those that are non-indigenous. Please contact us if you have suggestions or updates.

Source: Ethnologue

Groupings of individuals entirely according to language spoken. One language group equals one ethnic group, using this method. This grouping of individuals is appropriate for language-based outreaches (literature distributions, radio, recordings, etc.) Also appropriate for church planting / discipleship in many cases, but not all cases. For the related article about how people groups are defined, click here.

Source: Joshua Project

Within each Affinity Bloc are a number of more closely related peoples which, for strategic purposes, may be clustered together. These relationships are often based on a common identity of language and name but sometimes on the basis of culture, religion, economy, or dominance of one group over another.

Almost all People Clusters have total populations of over one million. It is likely that each People Cluster will need an international partnership of Christian churches and agencies for the effective evangelization of each constituent people group.

Sample People Clusters in sub-Saharan Africa.   Map source:  Future of the Global Church

People Clusters are the second level of the hierarchical Ethnic Peoples tree and use the Joshua Project code PeopleID2 which is related to the Harvest Information Standards code ROP2.

Learn more:
Source: Patrick Johnstone

"A significantly large group of individuals who perceive themselves to have a common affinity for one another because of their shared language, religion, ethnicity, residence, class or caste, situation, etc., or combinations of these. For evangelization purposes, a people group is the largest group within which the Gospel can spread as a church planting movement without encountering barriers of understanding or acceptance."

In many parts of the world lack of understandability serves as the main barrier and it is appropriate to define people groups primarily by language with the possibility of sub-divisions based on dialect or cultural variations. Groups defined by language are usually called "ethno-linguistic" people groups.

In other parts of the world, most notably in portions of South Asia, acceptance is a greater barrier than understandability. In these regions, caste, religious tradition, location and common histories, plus language may define the boundaries of each people group. These South Asian groups are often called communities or jati people groups.

Joshua Project uses the terms "people", "people group" and "ethnic people" synonymously. However, others may distinguish between the terms.

“There has been constant debate over the classification of ethnic groups. Membership of an ethnic group tends to be associated with shared cultural heritage, ancestry, history, homeland, language or dialect, the term culture specifically including aspects such as religion, mythology and ritual, cuisine, dressing style, etc. By the nature of the concept, ethnic groups tend to be divided into ethnic subgroups, which may themselves be or not be identified as independent ethnic groups depending on the source consulted.” (From Wikipedia article List of contemporary ethnic groups)

Joshua Project people groups are coded with a unique PeopleID3 value. Often the acronymns PGAC (People Group Across Countries i.e. without considering political boundaries) and PGIC (People Group In Country) are used. For example, there is one Uyghur ethnicity (PGAC), but the Uyghur reside in over 10 countries e.g. the Uyghur in China (PGIC). People group lists have traditionally used PGIC counts.

People groups are the third level of the hierarchical Ethnic Peoples tree.

Learn more:
Source: 1982 Lausanne Committee Chicago meeting, Joshua Project and Wikipedia

This counts a people group for each country it lives in. For example, the Tatar live in 21 countries, primarily in Central Asia. They would be counted 21 times.

The total number of peoples-by-country is the most common answer to the question "How many people groups are there?" Global people group databases have traditionally been People-Group-In-Country (PGIC) lists.

People-Group-in-Country is the fourth level of the hierarchical Ethnic Peoples tree and use a combination of Harvest Information Standards people code (ROP3) and country code (ROG3).

Learn more: Source: Joshua Project

A unique five digit code used to identify a people group across all countries in which they live. The People ID allows viewing the full picture of one ethnicity regardless of where they live. For example, see the Hausa (12070) or the Persians (14371).

Cross-reference tables to the Registry of Peoples (ROP) and (CPPI) are available upon request

Source: Joshua Project

Open Doors International ranking of persecution of Christians by country. The top 50 countries are ranked (1 = highest level of persecution) based on the World Watch questionnaire. The questionnaire contains 49 questions covering various aspects of religious freedom, differentiating between the legal, official status of Christians and the actual situation.

Attention is paid to the role of the church in society and the current situation facing individual Christians. Factors that may obstruct the freedom of religion in a country are also taken into account.

The aim of the list is to paint a realistic picture of religious persecution in a country. A point value is assigned depending on how each question is answered. The total of points per country determines its position on the World Watch List. Areas without significant persecution do not have a ranking.

Source: Open Doors International

An estimate of the number of pioneer workers needed for initial church planting among unreached people groups by country. Estimates are calculated only for unreached people groups and are based on ratio of 1 worker for every 50,000 individuals living in an unreached people group by country. Some workers may already be onsite. Country estimates are a summation of the unreached people group estimates.

Many more workers are needed beyond this initial estimate.

Source: Joshua Project, Finishing The Task (FTT) and Beyond

May be referred to alternatively as Majority / Minority languages. If significant numbers of individuals within one people group speak language A as their main language, and other individuals speak language B as their main language, Joshua Project marks the language with the most speakers (sometimes an estimate) as the Primary language for the entire people group. Other languages spoken are marked as Secondary languages.

Note that a language marked as Secondary for the entire people group may in fact be the main language for certain individuals.

In South Asia each people group may speak dozens of languages, and understanding what we mean by primary and secondary languages is essential.

Note that marking languages as primary and secondary does not refer directly to the degree of bi-lingualism in a people group, although it implies bi-lingualism is occurring.

Learn more:
Source: Joshua Project

The religion with the greatest number of adherents in this people group. Usually more than half the people group follow this religion, but not always.

People groups are categorized in eight primary religions:

  • Buddhism (Mahayana, Theravada, Tibetan)
  • Christianity (Anglican, Independent, Protestant, Orthodox, Marginal, Roman Catholic, Other)
  • Ethnic Religions (Ancestor Worship, Animism, Chinese Folk, Daoism, Shintoism, Traditional, etc.)
  • Hinduism (Vaishnavism / Vishnu, Shaivism / Shiva, Shaktism / Devi, Smartism)
  • Islam (Sunni, Shia, Sufi, Syncretized)
  • Non-Religious
  • Other / Small (Baha'i, Druze, Jain, Kirati, Mandaeism, Sikh, Zoroastrian, Other)
  • Unknown

For a listing of all primary religions, click here.

Source: Joshua Project

These are codes for peoples, geographic places and languages that allow key missions information to flow between various sources. Each kind of information is classified in a "registry" and then there are several hierarchical levels with each registry.

Registry of Geographic Places (ROG) Interactive Geographic Places tree.
  • ROG2 = Regions / Continent code [Example: 3]
  • ROG3 = Country code [Example: CH]
  • ROG4 = First Admin / Province code [Example: CH14]
Registry of Languages (ROL)
  • ROL3 = Language code [Example: rus]
  • ROL4 = Dialect code [Example: 16118]
Registry of Peoples (ROP) Interactive Ethnic Peoples tree.
  • ROP1 = Affinity Blocs code [Example: A007]
  • ROP2 = People Clusters code [Example: C0216]
  • ROP3 = People Group code [Example: 110033]

Codesets are at the Harvest Information Standards website.

Joshua Project ID (PeopleID3) In January 2010, Joshua Project began using the following for people coding and web linking:

  • PeopleID1 = Affinity Blocs code [Example: 11]
  • PeopleID2 = People Clusters code [Example: 137]
  • PeopleID3 = People Group code [Example: 10125]

A segment of a people group that probably does not need a unique church planting effort. Reaching the parent people group will likely reach all the subgroups. The Gospel can flow between subgroups without encountering significant barriers of understanding or acceptance.

On-site workers may determine that unique church planting efforts are in fact needed among a subgroup. In those cases Joshua Project will elevate the subgroup(s) to the distinct people group level.

The Joshua Project default is to make any entry a distinct people group unless field sources indicate that an entry is more likely a subgroup. Subgroups are almost exclusively in South Asia and particularly in India. People groups in other parts of the world occassionally have subgroups. For example, see the Aimaq in Afghanistan or the Akha in Laos.

Source: Joshua Project

An unengaged unreached people group (UUPG) has no known active church planting underway. According to the IMB Global Research Office: "A people group is engaged when a church planting strategy, consistent with evangelical faith and practice, is under implementation.

In this respect, a people group is not engaged when it has been merely adopted, is the object of focused prayer, or is part of an advocacy strategy." At least four essential elements constitute effective engagement:

  • apostolic effort in residence;
  • commitment to work in the local language and culture;
  • commitment to long-term ministry;
  • sowing in a manner consistent with the goal of seeing a Church Planting Movement (CPM) emerge

All unengaged unreached people groups (UUPGs) are by definition unreached people groups (UPGs). All unreached people groups (UPGs) are not necessarily unengage; many are engaged. Put another way, all UUPGs are a subset of UPGs.

Joshua Project primarily tracks unreached people group (UPG) information. Joshua Project hopes to keep a balanced focus on the many, technically engaged, but still highly unreached people groups. See Keeping Large Unreached People Groups in Focus.

For further information about unengaged unreached people groups, please see Finishing The Task (FTT). Joshua Project works closely with Finishing The Task in support of their mission to highlight unengaged unreached people groups (UUPGs).

Source: IMB Global Research Office and Finishing The Task (FTT)

An unreached or least-reached people is a people group among which there is no indigenous community of believing Christians with adequate numbers and resources to evangelize this people group without outside assistance.

Joshua Project uses the terms "unreached" and "least-reached" to mean the same thing. The terms are used interchangeably on this website.

The original Joshua Project editorial committee selected the criteria less than or equal to 2% Evangelical Christian and less than or equal to 5% Professing Christians. While these percentage figures are somewhat arbitrary, "we should not underestimate the significance of the small group of people who have a vision of a just and gentle world. The quality of a whole culture may be changed when two percent of its people have a new vision." - Robert Bellah, Institute for Advanced Study at Princeton University, originally quote in Psychology Today in the 1970s, currently quoted in Christianity Today Oct 2011: 42.

"A small body of determined spirits fired by an unquenchable faith in their mission can alter the course of history." - Gandhi

Learn more:
Source: 1982 Lausanne Committee Chicago meeting, AD2000 & Beyond Movement and Joshua Project


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