Rational budget reform has traditionally claimed the instrumental linkage between resource allocation and evaluation. Despite limited advances, this is still one of the aims of many current budget reform initiatives. This chapter deals with a number of issues related to the links between budgeting and new approaches to evaluation, taking into account the complexity of the public management context. Adapting budgeting to respond to the growing uncertainty and interdependence requires new criteria of success and evaluation as the basic framework of reference for management performance assessment. New approaches to accountability can also work as an incentive to encourage interactive learning.