The approach taken over the past decade to introduce minimum primary school standards in Vietnam is reviewed, with annual school audits that measured both input (quality) and output indicators. It describes a successful, context specific approach in which flexible data systems were used to support the evolution and adoption of a new set of standards. A rich multiyear data set has enabled impact analysis, equitable investment planning and test hypotheses on the variables within the "black box" of a classroom that influence learning. Institutional challenges presented in mainstreaming and evolving standards are contrasted with international best practice on raising standards. (Contains 4 tables and 9 figures.)