But those establishments, with their shaded lamps and handwritten signs advertising "beauty salon" or "massage parlor", sometimes offered other services and, warranted or not, the women who worked in them earned an unenviable reputation. "Many people considered women who worked in beauty salons to be promiscuous or, at the very least, they were not seen as good women," said Zhou.

The salons have also benefited from societal changes over the past few decades. "You have to understand that in the past, people actually despised the pursuit of beauty," said Shan Xiaoli, a 55-year-old who frequently visits beauty salons.

As a young woman, Shan wore the same dark-blue jacket and trouser combination as everyone else and even after China instigated its reform and opening-up policy in 1978, under the leadership of Deng Xiaoping, it still took time for people to accept that an interest in makeup, attractive clothes and the acceptance of beauty as a concept did not automatically mean a person was decadent.

"When I was younger, a girl who cared much about her appearance was seen as shameful," said Shan. "I only dared wear lipstick in my bedroom and quickly wiped it off when I left the room," she said, adding that cosmetics were rare in those days and that she was given them by an aunt who was visiting from Hong Kong.

Shan said she likes the feeling of being taken care of during the facial massages, which she regards as compensation for advancing years. "They won't make me young again, but they do make me feel more confident," she said.

Meanwhile, the privacy afforded by salons may also offer a partial explanation for the radical change in attitude towards the beauty industry in the past 10 or 15 years. Patrons feel they can let go and unburden themselves during treatment.

The salons don't just provide beauty services, according to Zhou, they also serve as a safe haven for many women, who enjoy the atmosphere and revel in their anonymity. "They tell us their secrets and relate stories about their relationships and families. They realize that we form a different circle than their family and friends and won't have an impact on their lives," she said.

And it's not just women. An increasing number of men are now visiting beauty salons - Banyan Tree Spa said that 45 percent of its customers are male - but their motivation is entirely different. "Like gyms, the salons are good places to build up guanxi (relationships), you know, and all businessmen need something like that," according to Zhang. The professional requirements of male customers are different, too. Unlike their female counterparts, men prefer body massages to skin care.

Unregulated, unsafe?

In addition to its reputation as a hotbed of sexual impropriety, the industry was also held back by concerns over safety. Although things have improved over recent years, the industry is still affected by those concerns to some extent.

One of the highest-profile cases of recent years is that of Wang Bei. The 24-year-old singer, a contestant on a popular TV talent program Super Girl, died in an anesthetic accident while undergoing plastic surgery in 2010. Her death garnered nationwide attention and led to calls for more stringent, and better policed, regulations.

One prominent critic, Zhang Huabin, a professor of plastic surgery at a medical school in Guangdong province, said that the increasing demand for cosmetic procedures had led untrained medical personnel to jump on the plastic surgery bandwagon, a practice he called "risky and irresponsible".

In 2010, the China Consumers' Association received almost 10,000 complaints about unsafe cosmetics, 20 percent of which were used in beauty salons. Small and medium-sized hair and beauty salons in remote areas were the focus of the most of the complaints. In its subsequent report, the CCA said the beauty industry still lacked regulation.

Rigorous training

In an effort to reassure the public and bolster the image of the industry, many beauty companies have instigated rigorous training programs for the thousands of women hoping to enter the industry.

"You have to book early to gain a place on a course to train as a therapist. If you leave it too late, there won't be any vacancies," said a trainer at the Shanghai Beauty Farm School, who declined to be named.

With 18 salons in the city, Beauty Farm offers one of Shanghai's most popular training courses for candidates looking for an entry point to the burgeoning industry. A qualified therapist can easily obtain the license to work required by the authorities, and those with outstanding marks get the chance to work in one of Beauty Farm's salons.

The training regime, which lasts two months and costs each candidate 4,320 yuan, is strict and very demanding. "If you want to enter a Beauty Farm salon, you have to work extremely hard," said the trainer, who pointed out that classes begin at 8:00 am and end at 9:30 pm. Moreover, an aptitude for the work is not the only important criteria. Candidates are required to present an above-average appearance and cracked hands or body odor are definitely not acceptable.

"I love the working environment here," said Vivien Xu, who works as a facial therapist at a recently opened spa center in the quiet and leafy Jing'an district of Shanghai.

Although the job can be both physically and mentally demanding - therapists require a fair amount of physical strength, and have to remember hundreds of hand positions used in massage, plus all the main acupuncture points - Xu said she loves the Spa's tranquil setting.

She decided to enter the beauty industry after graduating from Shanghai University of Traditional Chinese Medicine two years ago. "My academic background wasn't strong enough to get me a good job in a hospital, but I am satisfied with where I am now," she said, adding that she can earn as much as 6,000 yuan per month, and more important, the career path is attractive.

Zhang from Banyan Tree said the company provides its employees with job opportunities around the world, and also operates "fast-track" programs to encourage employees to constantly improve their skills. "For many young women, it's an ideal job. and believe me, they're lining up just to get a chance," she said.

Contact the reporter at xieyu@chinadaily.com.cn

Peng Yining contributed to the story.