Society is becoming more diverse owing to, among other factors, increased cross-border mobility, less-rigid gender roles, improved living standards and individualization processes. The diversity of lifestyles, value systems and experiences has consequences for social interaction, and the self-conception and internal integration of societies1; however, its precise impact is in many ways unclear. Intensified research is urgently needed as the effects of diversity are often the subject of controversial political debates.
Researchers are equally divided as regards the dangers and opportunities arising from growing societal diversity. Some sociologists have voiced doubts about whether individualized and ethnically diverse societies are capable of ever being integrated. In the United States, empirical studies have shown that ethnic diversity can be accompanied by low levels of trust among citizens and in societal institutions2,3. However, other studies have shown that regional economic dynamics are improved by population heterogeneity and a climate of tolerance. Here, diversity is linked with creativity, openness and vitality; multicultural towns act as both magnets for the cultural and economic elite, and breeding grounds for new ideas4,5. The key difference between these positions lies within the assumed capacity of societies to constructively use the potentials arising from increasing diversity.
To date, knowledge about the factors that affect this capacity, and about how individuals, social groups and societies deal with diversity, is limited. Little is known about how social interactions are affected by diversity, how individuals experience diversity, and how it affects their thinking and actions. In particular, there is a lack of systematic comparative research on different constellations and contexts. This is the starting point for several lines of research focusing, for example, on cities as places where ethnic diversity is experienced in a concentrated form. How do people in different contexts experience ethnic diversity? Under what conditions does migration background, ethnic origin or ascription play a role in social interactions? What kinds of interactions occur across ethnic boundaries and when? What role does the immediate spatial context play, i.e. a more homogeneous or heterogeneous composition of the population of residential areas? What significance do these experiences, and direct interactions between people of different origins and lifestyles, have in terms of attitudes towards society?