Multilingualism implies the use of two or more languages by a society, community, family, or individual to fulfill certain purposes. This study determined language proficiency among multilingual Indo-Fijian primary school children who speak the languages Fiji Hindi, standard Hindi, Urdu, English, Fijian, and Fiji English in their speech repertoire. Policy states that Fiji has a transitional education system with English replacing the mother tongue as the medium of instruction in Class 3 (age 8-9). However, while standard Hindi and the Bauan Fijian dialects have been designated as the vernacular languages of Indo-Fijian and Fijian children respectively, children may have little knowledge of these languages. Both languages have been imposed by force of circumstances because they are vehicles for literacy while Fiji Hindi and the other Fijian dialects are pre-literate. This research determines primary school language proficiencies specifically for Indo-Fijian children whose mother tongue, Fiji Hindi, is a non-standard language of low internal status in the community. It identifies the variables which affect multilingual proficiency in this group and determines whether classroom practice reflects educational policy. This research has implications for mother-tongue education in societies where there is classical diglossia or substantial differences between the standard and non-standard dialects.