In recent years, school-based assessment (SBA) has been incorporated into the English Language subject of a traditional high-stakes public examination, the Hong Kong Certificate of Education Examination. As reactions from various stakeholder groups have been mixed, it was necessary to review this new practice. This paper reports on a study of 33 English language teachers who have been frontline SBA assessors. The study aimed to better understand (1) teacher-assessors' perceptions of the English SBA, (2) their professional development needs in relation to implementing SBA, (3) their perceptions of how students could benefit from SBA and (4) the pressing issues arising from the SBA implementation. The study found that, while many participants agreed that SBA could be beneficial to students' English learning, there was much room for improvement in all four aspects investigated. In particular, some problems identified at the very beginning of the implementation of the English SBA have still persisted.