Ways and reasons for utilizing decision support tools to inform decision making in environmental management were pondered last week by young scientists and doctoral students in a course organized by BONUS GOHERR in collaboration with the DENVI doctoral programme of the University of Helsinki. During the course, participants got acquainted with the theory and practice of Bayesian decision analysis and multi-criteria decision analysis. Moreover, methods for defining criteria for decision making based on environmental values were reflected. Usefulness of these tools to support participatory and collaborative decision making were illustrated by several case studies drawing from e.g. fisheries management, risks related to maritime oil transportation, ground water and land use, and maritime spatial planning. In addition to lectures, the participants practiced applying decision analysis in their own research.