The valuable role that science has to play in disaster preparedness and risk reduction is widely recognized and was highlighted during the development of the successor to the Hyogo Framework for Action for disaster risk reduction that was adopted in March 2015. However, there are many factors that limit how effectively science can inform both disaster risk reduction policy and practice. Understanding these factors and taking steps to overcome them require a broad view, and a comparative approach can be instructive. We focus on two projects that were independently completed by the authors: earthquake risk management in Bangladesh and flooding and wildfires management in the United States. We use each case to reflect on the implications of recent recommendations made by the Science and Technology Advisory Group (STAG) of the United Nations Office for Disaster Risk Reduction that attempt to increase the integration of science in disaster risk reduction policy making. We then use the STAG recommendations as a framework for integrating our independent case study findings. Despite the differences in the geographic contexts and hazards being considered, these examples broadly support the STAG recommendations. However, the fine details of the way in which science is used in decision making need to be given careful consideration if science is to fully support disaster risk reduction. Although our collective observations suggest that science is an important part of the disaster risk reduction (DRR) process, suggesting that it is “key to post-2015 DRR efforts” as the STAG recommendations do, may perhaps overstate the role that science is able to play.