Nautical tourism is a selective type of tourism that has proven to be extremely important for the economy of all European economies. Like tourism, nautical tourism is not an official industry, so we will not find it in the National Classification of Activities (NKD), but its sub-activities can be recognized at least to some extent. The NKD changes that occurred in 2007 somewhat obscured the sources of the nautical tourism subtype, but the insights and lines of development for researchers remained recognized. Accordingly, when assessing the importance of nautical tourism, observed from the aspect of official NCEA activities, this fact should be taken into account because it contributes to the official assessment of the achieved effects. Its effects are multiple, so indirect effects are estimated to be between 3-5 times higher in value than direct ones. In nautical tourism, the marina business is tied to the rental of vessels, and it could be said that these two business activities are in symbiosis, because they record a high degree of interdependence. However, the profiles of their business, as well as market performance, are significantly different, but this does not diminish their connection. Precisely this fact is important due to certain changes in the classification of nautical tourism, which will be only sporadically indicated in this paper. The special importance of the subtype of nautical tourism, especially in the conditions of the Croatian economy, has a strong SME character. It is this fact that is the key to this research. Therefore, SME (Small & Medium Entrepreneurship) character of marina business, observed from the research aspect, is interesting, because through the analysis of the business system one can recognize the level of SME development at the macro level. That is, in order for SMEs to develop, the concept according to which they are developed is important, which is proving to be a key problem in the conditions of economies in transition. The influence of the state, its role, the way of setting up the system according to which SMEs develop shows significant differences in economies in transition as in the developed economies of the European Union. Therefore, in this research, the Croatian and German systems will be analyzed, from which, in addition to important insights, it will be possible to conclude about the differences in the development of SME thinking, which is a key factor of in the development.