ABSTRACTThe uncertainties surrounding research, and the way such uncertainties and other characteristics of the research process complicate research cost benefit analysis, are discussed. Issues such as measurement of research costs, adverse research effects, benefits of research (political and otherwise) and the dimensions of research social costs, benefits and utility are examined. Aspects of the theory and practice of this type of analysis are considered, including assessment of the risk associated with conducting, or not conducting, any particular type of research and evaluation of its non‐measurable aspect