AS COMPANIES across the region prepare to celebrate a year of hard work, legal experts are warning bad behaviour at the office function can leave a legal hangover lasting long after the silly season.

Employees can be sacked over indiscretions while bosses face legal strife, including being sued for sexual harassment or negligence, if they are not responsible hosts.

The sobering message is one reinforced by industrial and employment lawyer Simon Millman, who stresses staff must remember it is a work function and all the usual rules apply.

"Avoid behaviour you would normally consider to be inappropriate," Mr Millman, of Slater and Gordon Lawyers, said.

He said employers must be mindful of their responsibilities for workers. This can include supplying food and non-alcoholic drinks on the night and being clear about the company's code of conduct beforehand.

Social media is another area fraught with danger and Mr Millman recommends employees be aware of their firm's policy.

"It's the 11am-11pm rule - if the photo is not going to be appropriate at 11am, it's not going to be appropriate at 11pm," he said.

Queensland University of Technology Professor Paula McDonald has done extensive research around workplace sexual harassment and says it is the top concern at office parties.

Prof McDonald, from the university's Business School, said everyone needed to be aware of what constituted sexual harassment and avoid crossing the line - regardless of the amount of alcohol involved.

"There are risks attached to the office Christmas party and unprofessional conduct that happens there

in because the court sees that employer-sponsored social functions are an extension of the workplace," Prof McDonald said.

Monitoring the amount of alcohol supplied and putting a time limit on the event are among the precautions she suggests managers take.

"I think there needs to be really clear communication and a reminder to employees that this is work and while they encourage people to have a good time that the usual standards of professional behaviour, which are expected in the workplace, should carry over to the social function," she said.