This paper is concerned with the practical implications of assessing the arts through talk. The use of talk in the assessment process was a focus of enquiry in the research project, ‘Assessing Achievement in the Arts’, from which the data in this paper originated. A sample of 25 teachers who were committed to the principle of formative assessment was recruited. They were provided with a schema for a structured assessment conversation. The teachers' assessment conversations with their pupils were recorded and analysed. The teachers had difficulty putting their ideas into practice. The difficulties described here centre on the way the teachers' pedagogical styles affected the quality of the conversations. Three elements emerged as being significant: (1) teacher perception of the pupil-teacher relationship, (2) teacher attitude towards his/her role as assessor and (3) the teacher's approach to what counts as valid knowledge in the classroom. Finally the issues raised by these difficulties, specifically the inter-active relationship between teacher and learner are discussed.