As demand for proficient English speakers increases worldwide, there is growing concern about the standard of English achieved by students during their schooling. With English teachers (rightly or wrongly) receiving much of the blame for a perceived decline in language standards, policy-makers are increasingly interested in the language-related competencies of English teachers: both their language proficiency (or ‘communicative language ability’, CLA) and their ‘knowledge about language’ (or Teacher Language Awareness, TLA). As a result, the assessment of English teachers’ language-related competencies has become more widespread. In any attempt to measure those competencies, however, several important interrelated issues have to be confronted. Some relate to the precise nature of the knowledge/awareness that English teachers have of the language they teach, and the difficulties inherent in setting/measuring standards of Teacher Language Awareness. Others concern the language model(s) of which English teachers are expected to be aware, and about which teachers themselves feel they should be aware. The present paper examines some of these issues. It begins by exploring the nature of TLA, and some of the challenges in TLA measurement. It then considers questions relating to the varieties of English which form models for TLA, with particular reference to Hong Kong.