This paper develops a relational analysis (drawing on the insights of historical institutionalism and economic sociology) of the ongoing process of radical health sector restructuring in New Zealand. The original 'reforms', based on a 'purchaser provider' split, are outlined so as to emphasize their politically consequential ambiguity: was restructuring about revitalizing an essentially public health system or about creating the basis for an eventually private health system with a residual state role? The actual process of restructuring is then traced, emphasizing the responses it has evoked from differently situated actors within the health sector as this is entwined with the political system. The focus is on explaining the largely unintended consequences that have resulted, including the abandonment or significant modification of most of the originally enacted forms of organization together with the emergence of new organizational forms, initiated by providers, and largely unanticipated by the restructurers.