In the workplace it often happens to observe skilled, rational but extremely insensitive leaders without a sense of guilt and remorse. In fact, these subjects have excellent leadership skills, are charismatic, skilled planners and organizers, are very good at influencing the behavior of others, generating a mixed climate between terror and admiration. Their action is often characterized by manipulation and exploitation with the aim of achieving ever higher goals which are what often guarantees their success and prestigious positions.

In private life and relationships with the opposite sex, they tend to put their charm,charisma and manipulative tendencies into play, reaching high levels of mating in the short term; with casual sexual relations, extramarital and fleeting relationships without a real interest in the partner. They are often attractive especially for people with fragile personalities, victims of disappointments in various areas of life who know how to make them feel good and desired, and then leave them after reaching their goal of pleasure.

Among the socially aversive personalities mentioned in Kowalski (2001), three are the ones that have attracted the most attention of scholars:

1) : the term, introduced in 1970 by Richard Christiebased on the writings of Machiavelli, indicates a manipulative personality, cold and controlled, with a low moral sense, self-centered and tending to deception;

2) the construct of subclinical or normal narcissism was proposed by Raskin and Hall (1979) in an attempt to define a subclinical version of the narcissistic personality disorder indicated in the DSM, and includes some indicators used in the original diagnosis: grandeur, sense of right, dominance and superiority. The existence of a subclinical form of narcissism is supported by strong scientific research.

3) the adaptation of the psychopathy construct to a subclinical sphere dates back to the studies of Hare (1985) and Lilienfeld &Andrews, (1996). The central aspects of the construct include high impulsivity associated with the search for strong emotions, low empathic ability and low presence of anxiety and remorse (it seems that psychopaths present an alteration in the functioning of the brain structures responsible for processing fear).

In 1998 in their studio, McHoskey JW, Worzel, Szyarto C. claimed that narcissism,psychopathy and Machiavellianism were more or less interchangeable terms to indicate certain aspects of personality in a non-clinical sample of individuals, all sharing a trait called "".

Subsequently, however, Paulhus and Williams in their 2002 study found sufficient data to demonstrate that the three dimensions were only partially super imposable and therefore had to be considered separately. In this study, the authors note that disturbed but not yet frankly pathological personality types are reported in the scientific literature,frequently characterized by the simultaneous presence of three pathological features: machiavellianism, narcissism and psychopathy; the latter present mostly in subclinical form.

The authors conducted a study of a sample of 245 students by measuring these three dimensions through different assessment tools (standardized questionnaires, self report tools and laboratory assessments). The results show that the three constructs of the personality, although they show some interrelationships - sharing some aspects and manifestations - nevertheless remain distinct and not equivalent aspects. The measure they seem to share without a shadow of a doubt is the dimension of "unpleasantness" measured through the Big Five Questionnaire (McCrae and Costa).

The aspects that unite the three dimensions of machiavellianism, narcissism (subclinical) and psychopathy (subclinical) are the following:

1) Subclinical psychopathy is distinguished by the low level of neuroticism (an indicator that measures the tendency to be anxious, pessimistic, stressed, angry,frightened and emotionally unstable).

2) Machiavellianism and psychopathy both show a low level of conscientiousness and morality.

3) Narcissism correlates positively with the presence of high cognitive skills.Narcissists and - to a lesser extent psychopath - share high scores indicative of self exaltation and a sense of superiority and "grandeur".

The authors conclude that the Dark Triad of personalities shows constructs that partly overlap but that nonetheless remain differentiated.

However, there remains a strong conceptual and empirical tendency to overlap between the three constructs of the Dark Triad; for example, some researchers have noticed how all three traits of the triad share characteristics such as:

· lack of empathy

· interpersonal hostility

· interpersonal aggression

The individuals characterized by the dark triad show, as we have seen, some distinctive traits that derive from subclinical forms of narcissism, psychopathy and from the characteristics of machiavellianism:

· handling

· instrumentalization of the other

· deception tendency

· emotional coldness

· absence of empathy and moral sense

· absence of remorse and fear

· search for strong emotions

· impulsiveness

· sense of grandeur and specialty

· sense of right

· desire for power and dominance

· exaggerated care of the physical aspect

· acute intelligence

· tendency towards aggression and hostility

These people move around the world more or less with impunity, and it is not at alldifficult to find them on the net among the disturbers (trolls), in the workplace - especiallywithin the management class, or between interpersonal acquaintances.

In fact, the famous "serial lovers" clearly show many of the characteristics of the dark triad:

· emotional coldness and disinterest

· exploitation attitude of the partner

· search for strong sensations

· tendency to change partners frequently

· they do everything to conquer the prey which is then used and"thrown away" without remorse

· search for sexual adventures and experiences to the limit

· abuse of drugs and / or alcohol

· inability to establish an intimate relationship

· lack of moral sense

· deceptions and lies

· handling

Research has highlighted the potentially destructive effect that these individualshave on the environment and their partners.