This bachelor thesis deals with the narcissistic personality disorder which is becoming an increasing problem of modern society. It presents clinical features of the pathological narcissism, its diagnosis and problems. Furthermore, the thesis describes the main theories of development of this personality disorder, the differences between different types of narcissists and the characteristics of their interpersonal relationships. Since the aim of this thesis is to look at this topic from the social work perspective, the emphasis is placed on the features of working with people with this disorder, as well as the knowledge and key skills that social workers should possess when working with them. Given the above, the thesis covers the area of individual and group psychotherapy, as well as the features of narcissistic divorce that social workers mostly encounter through the process of family mediation. Since one of the main roles of social workers is the protection of children’s welfare and their rights, the thesis concludes with the chapter on relationship between narcissistic parents and their children.