Hong-Kong is one of the most famous offshore jurisdictions in Asia and even the world. Businesses setting up there can enjoy easy access to the Chinese market and low tax (or no tax) for their corporate income. Hong-Kong is especially useful when expanding your business in an Asian country as a good location for a holding company. Opening a company in Hong Kong can be done quickly with low costs and a maximum of privacy.
If you want to know more on the basic procedure for establishing a company in HK please see: http://www.cr.gov.hk/en/home
For more general info on foreign investment in Hong Kong please access http://www.censtatd.gov.hk/hkstat/sub/sp260.jsp?productCode=B1040003.