## 5 Conclusions  
Rapid and effective response to threats to the normal functioning of humanity and the economy is one of the greatest challenges of the third decade of the 21 st century. To combat elements of unspoken hybrid warfare, it is necessary to expand existing surveillance systems, adapt solutions from other fields of knowledge unfamiliar to the maritime sector, or develop new systems from scratch based on the latest scientific advancements. The methods currently used for protecting maritime critical infrastructure primarily focus on visual and radio-electronic monitoring of supervised waters. However, existing approaches do not incorporate real-time analysis of available official databases, which prevents early pre-selection of potentially suspicious vessels. The presented method is based on a combination of the MCDA method and AIS technology, supported by continuous radio-electronic observation of the water area, and extended with access to official ship databases. In the next stage, due to the volume of data being processed, the use of artificial intelligence is planned to support basin surveillance. It would be the AI that performs the initial selection of vessels, which would then be further analyzed by traffic monitoring experts. The application of AI will require advanced IT technologies that either do not yet exist or are still in the early stages of development. The developed method is not a definitive tool for identifying illegal ship activities; rather, it is intended as a support mechanism for protecting critical infrastructure and assisting in post-incident investigations. The reliability of the method depends on the appropriate selection of the criteria set and the accurate evaluation of alternatives based on these criteria. A key factor is the choice of qualified experts to define the evaluation framework. In this study, the assessment team consisted of experienced captains and merchant marine officers. This method requires further development, particularly in securing official access to national and international databases. Such access, however, requires standardization and the implementation of a unified authorization system. The key aspects of the method's applicability include:  
* The possibility of using it in any sensitive maritime area;
* Acceleration of the vessel identification process;
* Facilitation of the selection of potentially dangerous vessels;
* Enhancement of the protection of critical maritime infrastructure;
* Improved protection of human life and the environment;
* Strengthened international cooperation in the field of safety and security at sea. The innovative aspects of this study include the expert research conducted, the development of vessel evaluation criteria, and the design of a comprehensive system that collects heterogeneous data on vessel anomalies, processes the information using preference functions, and generates results for the selection of high-risk vessels and early warning of threats to critical submarine infrastructure. The overarching goal of this study was to improve and ensure maritime security, and to counter emerging threats that have either not occurred before or only appeared on a limited scale. The implementation of the method developed by the authors requires further research, but it holds great potential for application in the offshore sector to protect the maritime sector. Conceptualization, M.W. and M.M. ; methodology, M.W. and M.M. ; software, M.M. ; validation, M.W. and M.M. ; formal analysis, M.M. ; investigation, M.W. and M.M. ; resources, M.W. ; data curation, M.W. ; writing--original draft preparation, M.M. ; writing--review and editing, M.W. and M.M. ; visualization, M.W. and M.M. ; supervision, M.W. and M.M. ; project administration, M.W. and M.M. ; funding acquisition, M.W. All authors have read and agreed to the published version of the manuscript. This research was funded by statutory research activities at the Maritime Universityz of Szczecin. Not applicable.