The purpose of this article is to propose a model for planning the development of the naval forces in a medium-sized state through a process of their accurate and effective modernisation, on the example of Poland. Taking up such a subject arises from the delayed results of the current modernisation efforts. In order to achieve the aim mentioned above, it is recommended to solve the research problem by defining a suitable methodology facilitating the planning of naval development. The working hypothesis states that the methodology for the planning development of the naval forces should define a scope of modernisation activities undertaken with the use of tools and methods typical of management and quality sciences. The Allies’ guidelines on acquisition of defence resources stated in the NATO standardisation publications have been also taken under consideration in the research analysis. This modus operandi allows the Authors to fill a research gap in an interdisciplinary approach toward planning the process in question. The study is of conceptual nature. However, it enables the creation of well - aimed and justified programmes for the development of the Polish Naval Forces. The article displays a new perspective in the research analysis, which was formerly conducted by Authors in the years 2020 and 2021, before the Russian invasion of Ukraine.