This study examines ethnic segregation of core discussion networks in the Netherlands. The analysis is based on Netherlands Longitudinal Lifecourse Study, a large-scale survey of the Dutch population aged 15-45 that contains an oversample of first-and secondgeneration immigrants from Turkey and Morocco, the two largest non-western immigrant groups in Holland. Results show that among Turks and Moroccans, more than 75% of the confidants are co-ethnic multilevel logistic models of these ego networks which suggest that ethnic closure in core discussion networks of Turks and Moroccans is stronger among women, foreign-born immigrants, those who live in immigrant concentration areas and those who are culturally more dissimilar to the Dutch to (i.e., who speak Dutch less well, who more strongly participate in Muslim practices and who identify stronger with their ethnic group). Results further suggest that the socioeconomic gradient in ethnic boundaries is due to both cultural and economic homophily.