South Korean women, tradition says, are hard-working, respectful to family, and know their place in Korea's Confucian hierarchies. But the country's rapid economic development has meant some startling changes below the surface of that conservative social structure. Perhaps the most controversial is the advent of Host Bars - all night drinking rooms where female customers can select and pay for male companions, sometimes at a cost of thousands of dollars a night. Originally set up to cater to off-duty 'hostesses' and female escorts, they're now proving popular with many other women too. The growth of the industry is throwing up new questions for South Korea's sociologists and politicians as they struggle to reconcile the country's traditional values with the effects of its rapid development. The BBC's Seoul correspondent Lucy Williamson reports.