This chapter describes the nature of real-time evaluation (RTE) as compared with more traditional approaches, context for the evaluation, the factors taken into account when deciding to conduct a RTE, and the challenges encountered so far. The economic crisis of 2008 triggered a global response of which the World Bank Group (WBG) became an integral part. The Independent Evaluation Group of the WBG felt the need to contribute evaluative knowledge to the response. The economic crisis of 2008 triggered a global response of which the WBG became an integral part. The global economic crisis has erased some of the gains in living standards achieved by the developing world during the ten years prior to the crisis. The chapter describes some the challenges faced in implementing a real-time implementation of the WBG response to the global economic crisis. It provides an illustration of the promise that RTE holds for effective learning and accountability in the context of complexity and uncertainty.