These data were used in order to (1) investigate the relationship between intergroup contact, perception of intergroup threat and ideological attitudes and behavioral intentions among members of ethnic majority and minority groups, (2) investigate the role of social norms in relationship between intergroup contact, perception of intergroup threat and intergroup attitudes and behaviors, (3) investigate the possible changes between aforementioned variables in one year period. One data set contains data collected in two time points on Croatian majority and four minority groups, students and their parent (only in the first time point) - cda1016_dat_integranorm_longitudinal.tab, while other data set contains data collected from two countries, Croatia and Serbia, in one time point on majority and minority students and their parents (cda1016_dat_integranorm_crossectional.tab).