In work “SWOT analysis – interpretation of the analysis of external and internal environment” we are examining the concept of management, defining internal and external environment as well as planning function. Management appears in all organizations as a key factor for achieving goals. The success of management will be defined with actors from the environment in which they work. Management can’t affect the external environment of management but on an internal level, it can affect completely. Management consists of five functions and one of most important is planning function. As the first function, planning and management became an inescapable part of management job. For company’s analysis, the most important method is the SWOT analysis. Companies should be doing SWOT analyses at least once a year because it will be useful to managers if they are able to carefully investigate strengths, weaknesses, opportunities, and threats, all to assure the company’s success. This work examines, as an example, the inner workings of the bookkeeping service ''Ratel''.