The main objective of this paper is to extract practical lessons on increasing tax revenue effort that are relevant to developing countries. Specifically, it focuses on insights from two dimensions: the political economy requirements to generate public support for reform and the technical factors (“nuts and bolts”) of substantially increasing tax revenue effort. General topics covered include the political economy preconditions that facilitate tax reform, how and by whom tax reform should be implemented, the timing of reform efforts, determinants of current tax effort, tax policy choice options, tax administration options, and the enhancement of tax morale and compliance norms. The paper also profiles successful examples of recent tax reforms from 29 countries worldwide. It concludes with lessons from both the literature and these countries’ experiences, empowering reform-minded politicians and administrators to shape their own jurisdictions’ strategies for increasing tax revenue effort.