The world's response to Indian Ocean earthquake and tsunami of December 2004 was unprecedented, and donations from all public and private sources topped US$13. 4 billion. Yet even for the most experienced of grantmakers, the enormous scope of this catastrophe posed an array of decision-making challenges. With the Tsunami Learning Project, Grantmakers Without Borders sought to find answers to these decision-making challenges. This document offers new tools for grantmakers when responding to natural disasters, exploring the role of both large and small grants in disaster response. It also explores what a social justice or rights-based approach in disaster response grantmaking might look like.