Some individuals think they are great and special people who should be admired and respected by others. Such people are often called ‘‘narcissists.’’ The term narcissism comes from the mythical Greek character Narcissus, who fell in love with his own image reflected in the water. In the extreme, narcissism can be a clinical disorder , however, it is also widely studied as a personality trait in non- clinical populations . The narcissistic personality is characterized by inflated views of the self, grandiosity, self-focus, vanity, and self importance . Narcissistic individuals have an exceptionally positive view of themselves, and the narcissistic personality is associated with a complex configuration of intra personal and interpersonal outcomes . As outlined below,there are many scientific puzzles in the area of narcissism research and a single-item measure of narcissism would give scholars a practical tool that could be used to obtain a better understanding of this trait.On the one hand, narcissism is associated with some positive intrapersonal outcomes. For example, people scoring higher in narcissism are high in creativity , happiness , and self-esteem[7,8], and low in anxiety [9,10] and depression [10,11].On the other hand, narcissism is associated with many negativeoutcomes such as being prone to defensive and self-protective strategies. When narcissistic people are faced with threats to their self-worth, concepts of worthlessness are immediately activated,and then quickly suppressed . In addition, after receiving negative evaluations they are likely to see problems with the evaluation technique or the evaluator rather than reflect on how to improve . Narcissistic people also have difficulty maintaining healthy interpersonal relationships [14,15], perhaps because of their relatively low empathy [16,17] and low commitment to relationship partners . Narcissists believe they are entitled to the admiration and respect of others, and, when they do not get it,they become angry and aggressive [19,20,21,22].Scholars have tried to reconcile these striking disparities by trying to understand the underlying dynamics of narcissistic cognition, affect, and motivation, within the context of their social interactions . They argue that to fully understand narcissism,we must understand both the grandiose (or overt) and the vulnerable (or covert) aspects of it, and how these change depending on others’ approval or disapproval.Some scholars see the grandiose and vulnerable aspects as existing simultaneously within single individuals. They see narcissistic people as experiencing ongoing vacillations of extremes of self-worth that are dependent upon situations (e.g. success versus failure) and others’ evaluations [4,23]. Other scholars conceptualize two distinct types of narcissism, with different people leaning toward more grandiose (overt) versus more vulnerable (covert)types. Vulnerable and grandiose narcissism both involve feelings of grandiosity, high self-preoccupation, and a strong need for admiration, but vulnerable narcissists appear to be more shy and fragile, and often experience shame and worry that others might negatively evaluate them for their self-focus (see , or a review).Some scholars argue that linking grandiose narcissism with overt qualities and vulnerable narcissism with covert qualities is erroneous, and that grandiose and vulnerable subtypes can both express themselves in overt and covert ways – yet these arguments seem to apply specifically to clinical populations . Regardless of how these aspects of narcissism are specifically defined, the distinction between grandiosity and vulnerability is important because they measure more obvious versus less obvious ways of being narcissistic, respectively.