This article reports a research project investigating the formative assessment practices of two teachers of Year 12 English in Queensland. This is a high-stakes year that is focused on summative assessment for certification purposes. In this school-based, externally-moderated, standards-referenced system, however, teachers are also expected to provide opportunities for formative assessment. Data are drawn from two case studies that focused on the formative assessment work of two Year 12 English teachers. Two types of data were gathered and analysed: interviews and formative assessment artefacts. The research produced a provisional framing of five elements that shape teachers' formative assessment practices in Senior English classrooms in Queensland: policy and local contexts, relationships, teaching philosophy and prior experience, assessment documentation and routines of practice. The paper concludes that teachers' formative assessment practices are subject to situational factors, and highlights that relationships are critical to teachers' understanding and practice of formative assessment. (Contains 1 table.)