In work “SWOT analysis – interpretation of the analysis of external and internalenvironment” we are examining concept of management, defining internal and external environment as well as planning function. Management is appearing in all organizations as a key factor for achieving goals. Success of management will be defined with actors from environment in which it works. Management can’t effect on external environment of management but on internal it can affect completely. Management is consisting from five functions and one of most important is planning function. As first function, planning of management became inescapable part of management business. For company’s analysis, most important method is SWOT analysis. Company’s should be doing SWOT analysis at least once a year because it will be useful for manager’s if they carefully investigate strengths, weaknesses, opportunities and threats to assure company’s success. In the work is processed practice example from the accounting service “Ratel”.