Purpose. To work out the method for activities efficiency assessment of the governing body’s task force under environmental emergency. In order to achieve this goal, it is proposed to apply an integrated approach that allows increasing the effectiveness of its work. Methodology. The method for activities efficiency assessment of the governing body’s task force under environmental emergency was applied which allowed determining the degree of its capabilities realization. To study this process, a systematic approach was used, according to which the governing body is considered as a complex system that has a hierarchical structure and is a set of functionally interconnected structural units, united in their activities by the shared goal, concept and action plan. Findings. As the task force’s activity basis, a reasonable decision was determined of the governing body’s head, at the development and implementation of which the task force’s work is aimed. The task force’s efforts coordination is carried out in accordance with the tasks, directions, areas, time and methods of tasks performing that are assigned to the subdivisions of the governing body. As the main factor in activities efficiency assessment, the training level of the governing body’s task force was determined, that stipulates its professional and personal features. Originality. The proposed method for activities efficiency assessment of the governing body’s task force is estimated using an integral index – the degree of its capabilities realization to perform tasks. In the mentioned method, the criterion for activities efficiency of the governing body’s task force is determined as a condition under which the quotient from division of the total capabilities realized by the governing body’s task force indicator by the indicator of its total potential capabilities is in the range 0.8–1. A diagram of the method for assessing the task force’s activities efficiency was elaborated, containing interrelated blocks (activities), direct connections and feedback, which generally characterizes the sequence and actions content of the governing body’s head when implementing the mentioned method. Practical value. An example of estimating the activities efficiency of the governing body’s task force to achieve the goal in terms of an integral index – the degree of its capabilities realization to perform tasks, which is calculated using the proposed method, was considered. The initial data for calculation were the main tasks performed by the environmental emergency response headquarters’ task force, standard time indicators and prescribed time for tasks performance designated by the governing body’s head. On this basis, an analysis of the headquarters’ actions on eliminating the emergency consequences connected with the blowing up of the Kakhovska HPP was carried out, its main tasks and features of the decision-making process in uncertain conditions were established. The directions of increasing activities efficiency of the governing body’s task force were elaborated, in particular by increasing their professional competence, implementing innovative approaches to the transformation of governing styles, rational tasks distribution.