This guide was developed after discussions within the evaluation community, and within ALNAP in particular, about how to strengthen evaluation of humanitarian practice, and how to foster more effective use of the Development Assistance Committee (DAC) evaluation criteria. The DAC evaluation criteria are currently at the heart of the evaluation of humanitarian action (EHA) - including within evaluations themselves and as part of agency guidance. However, several criteria are not well understood; their use is often mechanistic, and excludes more creative evaluation processes. The objective of this guide is to provide practical support on how to use the DAC criteria in EHA. It draws on good-practice material on evaluation and on EHA, including other guides, handbooks and manuals. The guide also draws on a questionnaire completed by 25 ALNAP Full Members, and on the work of the author on the ALNAP Review of Humanitarian Action. In order to maintain focus, the guide does not include significant detail on wider issues such as evaluation management, choice of methodologies or evaluation approaches. Also, the guide is not intended to provide in-depth details on the DAC criteria but rather to introduce the criteria to the reader, who can then follow up as appropriate. The guide was 'road-tested' by practitioners, and their useful feedback has been incorporated into this final version.