Employers of business travelers and work permit holders seeking to enter China for activities designated by the Chinese government as necessary economic, trade, scientific or technological activities can apply for an invitation letter from the Foreign Affairs Office in the district where the company is registered in China, which, once approved by the Foreign Affairs office, can be used to support a visa application at a Chinese consular post. Each Foreign Affairs Office may have different practice and requirements.
Previously, Foreign Affairs Offices in Shanghai only accepted invitation letter applications for foreign employees to come to China for the urgent/important business. But now if a foreign employee is already in China and her/his family members are overseas, the family members can apply for the invitation letters separately to support their China entry visa applications.