This report presents the findings of an effectiveness review carried out on Oxfam's response to the 2012 cholera response in Sierra Leone that was undertaken through the application of Oxfam's Humanitarian Indicator Tool. Overall the response scored 87% and met or almost met nine of the 10 standards that were relevant to the response. This provides a measure of a high quality response, clearly exceeding the 60% cut-off point. This was based on deploying experienced specialist emergency staff from the global pool in good time, applying Oxfam's cholera response guidelines effectively and building on the core programme's profile and experience. The relationships with community-based structures, the Government and UN that had been developed through this work enabled greater efficiency and speed. Identified weaknesses in preparedness measures which slowed the initial response have been rectified, developing an updated cholera contingency plan with clear triggers aligned to the cholera guidelines and reinforcing the importance of cholera preparedness central to the urban WASH programme.