"This is only the beginning of a long-term trend," said Ma Jiantang, director of the bureau. "The working-age population in China will decline gradually but steadily every year until 2030."

With more bargaining chips on their side, workers are becoming more outspoken.

Strike continues at IBM plant in China

Workers continue strike over unpaid benefits

"There have been more and more strikes in recent years because we lack a channel for both sides to sit down and address problems reasonably. It's necessary to have relevant rules as soon as possible because we can't expect the authorities to take care of every demonstration staged by factory workers," said Huang Qiaoyan, a lecturer at the School of Law of Sun Yat-Sen University.

"Wise employers would back the ordinance because rules mean order," Huang added. "Even when negotiation bears no fruit, the issue can be disclosed for public judgment. Otherwise, the weaker side - usually labor - gains the most sympathy."

Huang said that most of the employers she has met misunderstand the new ordinance. "Especially Hong Kong businessmen - they are used to the top-down management style. They miss the 1980s and '90s, when workers were so poor they were easily satisfied with little pay."

"Manufacturers are complaining only because they have been in the country for so long they are spoiled by the old rules," said Dickson Ho, principal economist of the Hong Kong Trade Development Council.

"Labor rights protection has seen consensus everywhere else in the region. Even low-cost production bases such as Cambodia and Myanmar have signed agreements with the International Labour Organization, because the developed world doesn't want to buy sweatshop products. Hong Kong employers need to catch up."

Huang indicated that Guangdong's collective contract ordinance is in line with the requirements of the ILO. "It's fair on both sides. Any country that applies democratic management has such rules. There's nothing excessive."

"Times have changed," she said. "A new generation of migrant workers knows better about their rights and demands more. The employers' attitude is critical in settling disputes with workers. People will certainly vote with their feet against those who are immersed in the memory of the old days."