ENThis article addresses the problems of uncertainty of information when conducting research on countries currently at war. During the spring of 2024, we conducted interviews with social sciences researchers from Sweden, Poland, Estonia, Latvia, and Lithuania studying Ukraine after Russia’s full-scale invasion in 2022. We asked what challenges they experienced during their research, and how they coped with research quality and reliability of sources in their work. Our findings suggest that researchers struggle with geographical and chronological distance to the research subject, cultural knowledge, language barriers, their positionality, and unreliability of sources. Most of these problems are practical in nature, yet they have negative consequences on the quality of analysis of the research. To overcome these uncertainties, the researchers used various coping strategies: lowering expectations, avoiding unreliable information, and reshaping research questions. Nevertheless, researchers reported that unreliable information is often used informally anyway, which is a problem for the quality of results. Although there is no panacea for handling uncertainty of research during wartime, we suggest a possible way to move for ward: to apply the method of source criticism from historical sciences to social science research on current conflicts. We adapt historical source criticism methodology to this purpose and present a matrix to guide researchers who study contemporary wars. Keywords: peace and conflict studies; Ukraine; security policy; history; social sciences; methodology.