Codemixing of Cantonese Chinese and English is a common speech behaviour used by bilingual people in Hong Kong. Though codemixing is repeatedly criticised as a cause of the decline of students' language competence, there is little hard evidence to indicate its detrimental effects. This study examines the use of mixed code in the context of the home setting, school setting and leisure activities. The data are complied from a questionnaire completed by 160 Hong Kong teachers and students. Subjects recorded their awareness of their frequency and purposes of using a mixed code communication style. Results showed that codemixing was frequently used by the subjects. Findings suggested that codemixing performed certain communicative functions and was used for various practical purposes. Codemixing appears to be a customary component of a bilingual society. No matter whether people dislike or prefer it, codemixing continues to exist and satisfy bilingual speakers' communicative needs. Administrative sanctions may not be effective. [Copyright of International Journal of Bilingual Education and Bilingualism is the property of Routledge. Full article may be available at the publisher's website: http://dx.doi.org/10.1080/13670050608668640 ]