The paper describes the approaches to the definition of “staff crisis”, as well as analyses the theoretical aspects of the toxic management. It is also disclosed the specificity of an activity of managers with disruptive behaviours and of the toxic manager model, which will contribute a deeper understanding and studying toxic leadership problem. In addition, the authors present the experience of an implementation of the leaders' evaluation system and develop a technique that enables to identify the toxic manager and to assess his toxicity level. An important advantage of this study is its contribution to the understanding of the causal relationship between the staff crisis and toxic leadership. The practical significance of the given study is defined by the search and development of management tools to identify the toxic leaders, as well as to prevent the occurrence of the staff crisis caused by the use of toxic methods of human resource management in the organization.