Rude and drunken conference guests are abusing and threatening hotel staff more than ever before, with women behaving more badly than men, according to a conference booking company.

Staff are sometimes "spoken to like slaves" and some leave the industry because delegates behave so badly, says the Banks Sadler survey, which questioned 114 hoteliers.

About 40% of the hoteliers complained of bad behaviour during business events.

A minority of women troublemakers are highlighted as the worst offenders, leaving toilets in a disgusting state, being sick in bed, and flirting embarrassingly when drunk.

Banks Sadler added that hoteliers "are increasingly embarrassed by the degree to which some delegates take advantage of company hospitality and eat and drink to excess, with results in a range from fighting to having sex in a corridor."

Among the worst reported incidents of 1998 were a man who went behind the bar and urinated in as many glasses as possible and an orgy in a hotel suite which resulted in the room being soaked with water.

Penny Thomas, director for Banks Sadler, said: "The key to the problem appears to be first, the corporate policy of offering free alcohol, because fewer incidents occur when delegates pay their own way, and second, the acceptance of very late drinking."