The pre-feasibility studies for the Project were completed by Transport Engineering Design Incorporation (TEDI) in April 1996, and by the Express Highway Research Foundation of Japan in June 1996. Upon request of the Government of the Socialist Republic of Vietnam, the Government of Japan through the former Overseas Economic Cooperation Fund (OECF, now renamed Japan Bank for International Cooperation - JBIC) decided to provide a loan to finance the construction of the Project. The first loan agreement between the two governments was concluded on March 26, 1997 and the second loan agreement on March 30,1999.

The executing agency of the Project is the Project Management Unit No.85 (PMU85) under the Ministry of Transport (MOT) of the Government of the Socialist Republic of Vietnam. On December 12, 1997, PMU85 signed a contract for consulting engineering services for the Hai Van Pass Tunnel Construction Project, with the joint-venture of Nippon Koei Co., Ltd., Japan and Louis Berger International Inc., USA, in association with Transport Engineering Design Incorporation (TEDI), Vietnam (the Consultant). The Consulting Services consist of the following five components:

1) Special Survey

2) Detailed Design

3) Contract Tendering Assistance

4) Construction Supervision

5) Training and Technology Transfer

Following the issuance of the Notice to Proceed on January 2, 1998, the Consultant officially commenced the Services on January 20, 1998.

The Special Survey, the major objective of which is to select the most desirable route of the Project through detailed comparison of route alternatives, was completed with the submission of the Special Survey Report on April 23, 1998.

The Detailed Design commenced at the end of February 1998, and was substantially completed with the transmittal of the draft bidding documents for five contract packages by the end of July 1999. The Services during the Tendering Stage were commenced with the assistance for prequalification evaluation for Contract Package-I: Tunnel Civil Works conducted in June 1999. Tendering for Packages IA and IB was completed with the signing of Contracts on August 17, 2000 and the Project entered the construction stage in parallel with the tendering for the remaining packages.