Sydney on a world scale is a significant city of immigrants, having 1 020 000 overseas-born in 1991 and over 900 000 second-generation persons. The Australian 1991 Census included detailed questions on birthplace, language spoken in the home and English language competency. This allows us to measure the extent of immigrant segregation in Sydney on a more reliable basis than has hitherto been possible. With the exception of the populations born in the former Indochina, the Asian, Middle Eastern and Latin American groups were not more segregated than the more concentrated continental European groups. For almost all groups, the term segregation is inappropriate. Nevertheless, some of the ethnic concentrations are large and, in western Sydney and the inner southern suburbs, higher proportions of persons with limited English, lower incomes and no jobs reside in concentrations than elsewhere. Economic difficulties are being experienced, more so in several concentrations than among compatriots elsewhere. The concentrations, however, are not the cause of disadvantage and application of the term ghetto, or even enclave, to these concentrations is inappropriate and may contribute to the negative stereotyping of groups.