Peer reviews have brought many issues to the attention of the Development Assistance Committee over the last five years. This chapter retains twelve of the more prominent examples of the lessons learned or reconfirmed over the period concerning effective aid management to achieve development results. Lessons at the level of strategy are: i) find the appropriate legal and political foundation; ii) manage competing national interests; iii) achieve greater policy coherence for development and iv) invest in delivering, measuring and transmitting results of aid-financed activity. Organisational management lessons are: v) identify a leadership structure that works; vi) deal with institutional dispersion, vii) manage contributions to multilateral institutions and viii) decentralize management to the field. Lessons concerning management of delivery are: ix) manage the scaling-up of development aid; x) maintain a focused approach towards countries and sectors; xi) emphasise performance-based management, evaluation and quality control; and xii) make human resource management a priority.