A massive rockslide at Åknes in the Stranda municipality in western Norway would have dramatic consequences, as the tsunami triggered by the slide would endanger several communities around Storfjorden. Site investigations, offensive monitoring and a warning system for the potentially unstable rock slopes were implemented to reduce hazard and consequences. As part of hazard and risk assessment, event trees were constructed by pooling the opinion of engineers, scientists and stakeholders. The objective was to reach consensus on the hazard, vulnerability and elements at risk (consequences) associated with a rockslide and tsunami, quantify the hazard (probability of a rockslide and tsunami occurring) and the potential losses (human life and material and environmental damage). The probability of occurrence and the risk were obtained through a consolidation of all the branches of the event trees. The event tree analysis results in a map of the risk for the residents for the municipalities close to Åknes. The paper presents the event tree analysis process and some of the preliminary results achieved on the hazard associated with the failure of the Åknes rock slope.