Pareto analysis is a versatile tool used to prioritize and solve quality problems. The principle is equally valid for the economy, health systems, small business and personal life. The monograph presents the essence of the Pareto principle, respectively the Pareto diagram. Describes a methodology - road map and technical aspects for constructing the Pareto chart (author's project). Examples of application of the concept in the economic sphere and health care are presented. Author's studies are attached to evaluate the contracted medical activities, the surgical activity and the resources in the morbid area. The health market has been studied. A management model is offered. The monograph is a practical guide for situation management at all levels of the health system, including in an epidemiological setting, also the management of cases with COVID 19. The monograph will be useful in the daily work of health care managers as well as other managers.