How do you spot the psychopath among your work colleagues? Professor Robert Hare, of the University of British Columbia, is a world expert on the "snakes in suits" who scale corporate ladders with consummate ease.
He delivered a public lecture on psychopaths at work in Belfast on Wednesday, in the run-up to a two-day conference organised by the British Psychological Society (BPS).
"Corporate psychopaths" use arrogance and superficial charm to scale the top of the ladder, knocking off whoever gets in their way, Prof Hare explained.
"White collar psychopaths will defraud people of their life savings, then quite happily go to the Mediterranean, have a villa and never give it a thought."
He estimates that one in 100 people in North America are psychopaths. You do not have to be Hannibal Lecter to fit into the profile.
"People might say he or she is charismatic, high profile or 'gets things done'. We have a whole series of euphemisms for the individual who may be self centred, grandiose, lacking in empathy and does not give a damn about everybody else," he added. Predators
"Think of Robert Maxwell who destroyed thousands of lives," he said.
Such people are social predators who do not get bothered by ordinary social anxieties. They are self serving individuals, he explained.
Their only concern is food. They see the world as one large watering hole. Their resources are sex, power and money.
With New York psychologist Dr Paul Babiak, Prof Hare has developed a new 107-point questionnaire to identify which desks those smooth-talking "snakes in suits" might be hiding behind.
The "B-Scan", which stands for Business Scan, was designed by them.
It follows on from the "P-Scan" which is now considered to be the standard test for detecting criminals with psychopathic leanings.
The test involves interviewing people working with the person concerned to get a so-called 360 degree assessment of their personality.
The two experts' book, Snakes in Suits: When Psychopaths go to Work, is currently with the publisher and should be finished by the end of this year.
The two-day Belfast conference was organised by the NI branch of the BPS. Its theme is: Protecting the Public - The Assessment and Management of Dangerous Offenders. BBC News