The Scottish chartered teacher programme (2003-2011) is an important example of a national policy designed to support the development of "accomplished teaching". This paper provides an account of the emergence of the programme before discussing how the impact of such a scheme might be assessed and thus rendered accountable. The difficulties of developing valid and reliable methodologies for ensuring accountability are explored, including an account of a pilot research project and an indication of what the international literature may reveal about such aspirations. The paper concludes with a summary of four major challenges facing researchers who wish to offer insights that are of use to policy-makers and practitioners.