High stakes testing has been long established in the English school system. In this article, we seek to demonstrate how testing has become pivotal to securing the neo-liberal restructuring of schools, that commenced during the Thatcher era, and is reaching a critical point at the current time. Central to this project has been the need to assert increased control over teachers' work and this is being achieved through a pincer movement of marketisation and managerialism. Both of these "policy technologies" require the value of individual teachers' work to be measured and quantified, and in this article we seek to demonstrate how high stakes testing underpins these processes. The article concludes by making the case for reclaiming teaching as a professional process, within the context of education, as a public good and conducted in a public space.