LÖST: Lessons from Maritime Total Defence Exercises DSM 2025

The LÖST project documented and analysed the practical sub-exercises conducted as part of Total Defence Exercise DSM 2025. Through onboard and simulator observations, interviews and surveys, the project identified key lessons from the planning, execution and evaluation of the exercise.

The study found that the exercise strengthened cooperation between civilian and military stakeholders and improved understanding of roles, responsibilities and decision-making processes during heightened preparedness. The findings also highlight the importance of realistic scenarios, effective time management and structured debriefing in developing operational capability.

The project identified opportunities for improving future exercises, including greater realism, increased uncertainty within exercise scenarios, and a stronger focus on operational training for masters and bridge teams. The lessons learned can support the continued development of the shipping sector's total defence capabilities and provide guidance for other sectors planning similar preparedness exercises.

The project was carried out by RISE in collaboration with the University of Gothenburg and funded by Lighthouse.