Dr Hughes, originally from Canada, said New Zealand has one of the "most toxic" workplace cultures she has seen -- exacerbated by workers avoiding conflict and suffering in silence.
"New Zealanders don't speak openly -- they don't like confrontation, so issues are left to fester," she said.
"Also, bullying has become so endemic here because we've come to accept it. We think it's normal to be in a toxic work environment.
"New Zealand has one of the highest rates of workplace bullying in the OECD, and one of the lowest rates of productivity -- the two aren't mutually exclusive."
Dr Hughes said workplace bullying is, in her experience, no respecter of professions -- and is present in everything from parliamentary offices to hospitality.
Contrary to stereotype, those most likely to be victims are not "weak", but are capable, confident and well-educated.
"For example, I had one manager see I had a pHD, and he said, 'I don't like people with higher education; you make me feel bad.'"
She said many New Zealanders fear asking for help as they are unable to afford legal services -- and colleagues are often afraid to speak on their behalf.
"If you're bullied, it's like you've got leprosy -- people think they can catch it."
In her role as consultant, she works with employees and managers to help resolve difficulties, and also runs seminars on achieving a positive workplace.
In many cases, clients have reported positive outcomes.
"A lot of people don't actually know what they're doing is bullying -- so we sit down with them and take an intense look at their behaviours and attitudes."
However, for many victims, the damage is already done, says Greytown counsellor Erin Bradley.
Mrs Bradley said a great many of her clients have experienced workplace abuse, and the consequences have been "devastating".
The main effects are depression, anxiety, loss of confidence and concentration, increased illness and, at times, "complete breakdown of normal functioning".
"When people are abused, this is experienced in the body as a threat.
"It causes limited access to the frontal cortex, which is responsible for decision-making and rational thought.
"This makes performing tasks very difficult."
Stuart Bruere, practice manager at Vet Services Wairarapa, said it is a manager's responsibility to create an inclusive and positive workplace culture.
Part of this, he said, was to ensure thorough background and reference checks are conducted on potential employees.
"My preference is to try very hard to find personalities that are not inclined to bullying," Dr Bruere said.
"Unfortunately, I have yet to find a reformed bully -- changing behaviours that have been established and rewarded from an early age is nigh on impossible."
