WORKPLACE sexual harassment is rarely a one-off incident, with serial offenders often persisting until somebody blows the whistle, a new book has found.

University of NSW Pyschology Associate Professor Jane Goodman-Delahunty has drawn together international studies on the topic for her book, Evaluating Sexual Harassment: Psychological, Social and Legal Considerations in Forensic Examination, due to be released next week.

"But in order for reporting to result in (an offender) desisting, there really has to be a high likelihood of apprehension and a very unpleasant sanction."

Recent figures published by the Human Rights and Equal Opportunity Commission revealed that 28 per cent of Australian women and seven per cent of Australian men have experienced sexual harassment at work.

"Sexual harassment in the workplace predominately affects women (and) seven in 10 cases of sexual harassment in Australia involve men harassing women," Prof Goodman-Delahunty said.

"According to the legal definition, sexual harassment takes place when there is coercion and somebody is only going to get a job benefit if they put out some sort of sexual behaviour on demand," she said.

sexual harassment. "But that doesn't mean that somebody is prohibited from paying somebody a compliment or from inviting them for lunch, coffee or dinner or from asking them out on a date," she said.

"That's certainly not harassment. It's only (harassment) when it becomes unwelcome, unwanted and persistent."

Sexual harassment affected bottom line costs for employers, albeit indirectly, she said. "Many employees who experience harassment are afraid to report it and aren't quite sure how to resolve it, and a lot of them just quit their jobs, which means that you then have high turnover rates."

Sexual harassment could also cause absenteeism among workers by affecting mental health and physical wellbeing, which in turn would lead to increased sick days.

While it was true that the instances of sexual harassment had increased over recent years, it was not "necessarily a bleak picture" for the future of the Australian workplace, Prof Goodman-Delahunty said.

"I think conflict can be fairly healthy, but it's probably a good idea to have mechanisms in the workplace to address these kinds of social conflict in an open sort of way," she said.

"I feel much more encouraged about an environment where that (conflict management) is feasible than one where there are just a whole lot of unspoken rules and where everything goes on behind the scenes.

"It's not that there is more harassment than before, it's just that people are a little more willing to report it, whereas before things tended to be swept under the rug."