During the last two decades of colonial rule, a wide gulf existed between policy and practice in Hong Kong's English-medium secondary schools: while English was the medium of textbooks, assignments and examinations, Cantonese and Cantonese-English mixed code were the dominant media of classroom communication. Although mixed-mode instruction was defended in some quarters, during the 1990s it was regarded in government circles as the main cause of unsatisfactory English standards. To eliminate mixed-mode instruction, and thereby ensure the consistent use of English or Chinese as teaching media, the postcolonial government introduced a controversial language policy in 1998 which permitted only 112 schools to remain English-medium, while most schools were forced to switch their medium of instruction from English to Chinese. This paper presents the findings of an investigation which aimed to gauge the extent to which the new policy has been translated into classroom practice in the 'reformed' English-medium stream. The findings indicate that teachers and students make greater use of English in the classroom than their counterparts during the era of 'mass' English-medium education, although, as might be expected, the language-learning experience provided in the 'reformed' English-medium stream generally falls short of the full immersion programme envisaged by policy makers. [Copyright of Journal of Multilingual and Multicultural Development is the property of Routledge. Full article may be available at the publisher's website: http://dx.doi.org/10.1080/01434630802147940]