Intergroup cohesion refers to relations of cooperation and respect between identity groups in a society. Where this cooperation breaks down, there is the potential for conflictual acts such as ethnically or religiously motivated killing, targeted assassination and kidnapping, acts of terror such as public bombings or shootings, or riots involving grievous bodily harm to citizens, with concomitant effects upon growth and development.
How different groups based on identity live together has continued to be one of societies’ main questions. All countries are marked by diversity, and in many cases there are socio-economic inequalities between groups based on identity rather than economic differences. While most of the time most groups live in harmonious relationships, distrust and hostility can exist, or emerge, often as a result of political mobilisation.
Social cohesion and conflict operate below the level of formal state institutions – albeit in implicit relationship to long-term political objectives and grievances – and can involve a diverse range of actors such as organised criminal groups, international terrorist networks, and ethnic or religious supremacist movements, as well as a diverse range of targets, including judges, public intellectuals, and ordinary citizens.
We measure intergroup cohesion using data on inter-group disparities, perceptions of being discriminated against, and feelings of distrust against members of other groups. ISD also use data on the number of reported incidents of riots, terrorist acts, assassinations, and kidnappings; agency ratings on the likelihood of civil disorder, terrorism and social instability; and reported levels of engagement in violent riots, strikes, and confrontations.
Data used in the 2020 index:
| Indicator | Variable name | Source | Countries |
| Do you have confidence in the local police force, feel safe walking alone at night, had money or property stolen or have you been assaulted or mugged? | law_and_order | World Happiness Report-Gallup | 134 |
| Rating of differences of opinion on major political issues in this society | soc polarization | Varieties of Democracy Database (V-Dem) | 177 |
| Log riots per log capita | riots | Cross-National Time-Series Data Archive | 132 |
| Log instances of guerrilla conflict per log capita | log guerrillas per log capita | Cross-National Time-Series Data Archive | 56 |
| Terrorist coded attacks based on a weighted average of the last four years (2016-2019) of 9 types | terrorist_attack_ave | Global Terrorism Database (GTD) | 138 |
| Global Peace Index rating on deaths in organized conflict at least 25 | deaths_in_conflict_rating | Uppsala Conflict Data Program (UCDP) | 38 |
| Fund for Peace rating on the “legacy of vengeance-seeking group grievance or group paranoia” | vengeance_rating | Fund for Peace/Fragile States Index | 178 |
| Average values of all indicators of the International Country Risk Guide | political_risk | International Country Risk Guide | 138 |
| Level of internal conflict, International Country Risk Guide rating | internal_conflict_rating | International Country Risk Guide | 140 |
| Risk of terrorism, International Country Risk Guide rating | terrorism risk rating | IEP Global Terrorism Index | 134 |