This article analyses findings from two studies conducted collaboratively across two educational settings, New Zealand and England, in 2001-2002. These studies examined the impact of national educational policy reforms on the nature of primary teachers' work and sense of their own professionalism and compared these impacts across the two countries. Adopting a policy ethnography approach, using in-depth interview data from samples of teachers in each country, it is argued that there have been discursive shifts in the meaning of the three key terms, autonomy, altruism and knowledge, embodied in the classical professionalism triangle. These shifts reflect policy-makers' moves from a "professional-contextualist conception" of teacher professionalism towards the "technocratic-reductionist" conception that accompanies neoliberal educational reforms in many countries. Teachers in both countries experienced increasing constraints on their autonomy as they became far more subject to "extrinsic" accountability demands. Whether these demands were perceived as enhancing or diminishing teacher professionalism depended on the manner in which they were filtered through the profession's defining quality, namely teachers' altruistic concerns for the welfare of the children in their care.