When the Western Harbour Tunnel (WHT) opened for public traffic on 30 April 1997, it has begun a new era in Hong Kong's transportation history. Not only does WHT reduce cross-harbour traffic congestion; it also stands out as the largest single transportation project in Hong Kong ever undertaken by the private sector.

The WHT project was franchised to Western Harbour Tunnel Company Limited (WHTCL) in 1993 by the Hong Kong Government, under a BOT (Build, Operate and Transfer) contract which continuous up to August 2023. According to the contract, the 30-year franchise includes the financing, design, construction, commissioning and operation of WHT. The Western Harbour Crossing Ordinance, which enacted in 1993, stipulates that WHTCL is entitled to collect tolls for the use of WHT till the expiry of franchise period.

WHT is a leading example of the benefits of privatization. The privatization of utilities and infrastructures has been widely recognized for the way in which it improves efficiency, lowers costs and frees up Government revenue for projects unlikely to be undertaken by the private sector.