Summary: Russia's full-scale aggression against Ukraine, which has been ongoing for over 3 years, and Russia's cyber war against Central European countries, are clear evidence of confrontational actions. This concerns the destabilization of the European security system by destabilizing the political and economic situation of individual countries in the Region and the whole of Europe. Finally, it concerns the destabilization of NATO. The article presents selected elements of knowledge on the subject of future warfare at sea in the context of the situation in the Baltic Sea. The concept of using multifunctional manned and unmanned platforms as an element of the Republic's rapid reaction forces in the South Baltic region is described. Examples of multifunctional platform concepts and the possibilities of their use are presented. Basing further considerations on the challenges that are the driving force of the development of technologies and implementations for defense, the critical maritime infrastructure protection system is described. The technological challenges related to the development of a critical maritime infrastructure protection system indicate the real possibilities existing in Poland for creating an innovative and effective rapid reaction force system integrated with the existing state security system. Purpose and research methods: The aim of the article is to present the basic features describing the future war at sea, taking into account strategy, tactics and operational capabilities. The following research methods were used: literature research, analytical research, parametric research of proposed solutions and research of operational capabilities of proposed solutions in conditions close to real ones, using methods on physical models and computer simulations in simulated operational conditions. Conclusions / recommendations: Some of the presented solutions may be important for the security of the state due to the possibility of further development of the concept as an element of the rapid reaction forces system, as in the case of the trimaran platform, and as a reconnaissance and covert action platform, in the case of AUV-Stealth platforms. Due to the increased defensive capabilities of the Navy and maritime special forces units, it is worth considering further development of the proposed concepts. It is proposed to use the proposed solutions in practice, after their prior implementation, as prototypes with the technological readiness level of PGT IX.