Abstract
Portfolios are widely used in the assessment of professional learning. Although claims are made that portfolios promote reflection, the nature of such reflection and the mechanisms that promote it in the portfolio process are not well understood. A four‐year action research project investigated a professional practice portfolio for high stakes assessment in a post‐graduate programme for special education resource teachers (RTs) that was preparing them for a paradigmatically different role. This paper focuses on the requirement to submit a personal theory (PT) statement in the portfolio. Although tension between the summative and formative purposes of the portfolio was evident for some RTs, a more comprehensive understanding of reflection was evident and many RTs reported that articulating their PT (often for the first time in their career) impacted positively on their ability to reflect on practice.