Finland and Shanghai are strong performers in the Program for International Student Assessment (PISA). The current study explored the similarities and differences in educational effectiveness between these 2 strong performers. To this end, 14 predictors representing student background and school process characteristics were selected from the PISA 2009 database. The results show that the Finnish educational system is more efficient in transforming given inputs, specially student background characteristics, into reading achievement, while the general condition of the school climate in Shanghai, in terms of value and effect size of the predictors, contributes a large part to its comparative strength in reading achievement. Suggestions for improvement at school and system level are given.