Abstract: Management decision is one of the main means of management. In a dynamic external and internal environment, management decisions must be made quickly. At the same time, the problem of the quality of decisions made becomes especially relevant. An organization that is able to make quality decisions has undeniable advantages. The quality of the decisions made at high speed of their development can be provided only by knowledge of the tools giving the chance to carry out various stages and operations of decisionmaking. In research in the field of economics and management a set of tools (methods, algorithms and techniques) is being accumulated and constantly replenished that can be used at different stages of the decision-making process. In management practice, various methods are used to solve different types of problems. Thus, well-designed methods and models are practiced to make solutions to standard problems; for weakly structured and unstructured problems, the use of a combination of methods is optimal. The complexity of management tasks continues to increase and determine the need for continuous development and improvement of methodological provisions, methods and guidelines. The scientific validity of decisions, their optimality depends, on the one hand, on the degree of perfection of the methods used in the process of development and implementation of decisions, on the other hand — on the level of knowledge and mastery of personnel management a set of methods. System analysis belongs to the formal methods used to justify and select optimal solutions, also it allows to identify the interaction of the components of systems and the strategy of their development. The article considers the issues of making an effective management decision by the head on the basis of system analysis. The author highlights the stages of making an effective management decision and the level of its responsibility. The materials of the article have a scientific and methodological character. The article discusses methodological approaches and methods for solving complex poorly structured problems in management.