Terminology is a central theme of debate about language shift in Malaysia's judicial system--sometimes seen as the last bastion of the colonial language. Advocates of more Malay in courtroom argument and professional practice often point to the Institute of Language and Literature's creation of thousands of terms to equip the national language for modern legal affairs. Those sceptical about the benefits of further reducing the role of English typically focus on lexical, discursive and cultural gaps between the Malay language and an adversarial system that continues to draw heavily on English common law. While supporting the view that comprehensive terminological reform is crucial if Malaysian language planners are to fully implement policies developed for the legal system more than two decades ago, this paper highlights the limitations of terminology as an engine of language shift. Planners have not only to make a corpus of terms available but to consider a range of linguistic and non-linguistic factors constraining their adoption into long-established professional discourses. (Contains 12 notes.)