The Italo-Greek ethnolinguistic minority, living in thirteen villages of southern Italy, marry largely amongst themselves but there are some intermarriages with native Italians. The majority of marriages are within the villages, but there is some marriage movement from one Italo-Greek village to another. Data on marriage and birthplace of parents and grandparents obtained by questionnaires to families of primary school children (aged 6–13 years) are analysed, to show the trends in breakdown of isolation over the last two generations.