The preparations for a Norwegian geotechnical research institute began in the years following the Second World War. The Research Council of Norway appointed a cooperation committee for geotechnical research.

Following are some important events in NGI's history:

NGI's professional development 
 

1950	The Office for Geotechnics was established as a forerunner to NGI while the final funding plan was established.
1951	Laurits Bjerrum from Denmark is headhunted from ETH in Switzerland, where he was head of the soil mechanics laboratory, and becomes the director of what is to become NGI.
1953	The Norwegian Geotechnical Institute (NGI) is officially established on the 1st of January    1953 by The Research Council of Norway.  Olav Folkestad from Ing. Bonde & Co was the chairman of the committee and becomes    the first chairman of NGI's Board of Directors.  NGI opens a department in Trondheim, lead by Ottar Kummeneje and Nilmar Janbu.
1956	NGI moves to new facilities in the 'Research Park' in Forskningsveien 1, close to the University of Oslo.
1957	GEONOR is established by NGI to manufacture and sell geotechnical laboratory and    instrumentation equipment. Nilmar Janbu is appointed professor at NTH (Technical    University of Norway).  NGI's office and laboratory in Trondheim is then transferred to NTH and eventually    becomes the Institute for Geotechnics in the Department of Civil Engineering.
1965	Laurits Bjerrum elected the President of the International Society for Soil Mechanics and Foundation Engineering (ISSMFE).
1967	The Terzaghi Library is opened at NGI. Karl Terzaghi, known to be the father of soil mechanics, donated all his files and archives and scientific material to this NGI based library.
1970	Some of NGI's divisions move to Sognsveien 72, together with The Research Council of Norway.
1972	After a resolution from the Norwegian Parliament in December 1972, NGI becomes responsible for avalanche research in Norway.
1973	Laurits Bjerrum dies. NGI's chief engineer, Ove Eide, becomes the new temporary    director.   The avalanche research station named Fonnbu is built in Grasdalen, in the mountainous    region in Western Norway.
1974	Kaare Høeg becomes the new managing director at NGI. Prior to the appointment he was a professor at Stanford University, CA, USA.
1978	NGI acquires its first main frame computer, the PRIME 400.
1983	The Institute for Rock Blasting Technique is embodied into NGI.
1985	NGI, and other Norwegian research institutes previously established and coordinated by The Research Council of Norway, becomes independent private foundations.
1989	NGI is awarded by ISSMGE (International Society for Soil Mechanics and Geotechnical Engineering) for 'Outstanding contributions in the field of offshore geotechnical engineering'.
1991	Suzanne Lacasse takes over the position as managing director at NGI after Kaare Høeg.
1993	NGI acquires ownership of the office and laboratory complex in Sognsveien 72 after The Research Council of Norway moves out. Now the whole of NGI is gathered under one roof.
1997	NGI sells the shares in Geonor AS, which now becomes a privately owned company.
2000	The Peck Library is opened at NGI, right next to the Terzaghi Library. Ralph B. Peck attends the opening himself.
2002	NGI is appointed Centre of Excellence by The Research Council of Norway with    responsibility for the International Centre for Geohazards (ICG).  NGI Inc. is established in Houston as a wholly owned subsidiary company of NGI.
2005	The NGI R&D scholarship fund is established intended for sabbatical leave and    specialization for NGI employees.   A new department office in Trondheim is established to maintain a closer connection with    the research environment in Trondheim and Central Norway.   The new research station Fonnbu is rebuilt and completed after the old field station was    destroyed in a fire.
2012	Lars Andresen takes over the position as managing director at NGI after Suzanne Lacasse.

 
NGI's professional development

1950

• NGI becomes internationally recognized and respected due to the research conducted to solve the problems of construction in soft clay. Focus was on soil investigation methods and laboratory equipment adjusted to Norwegian conditions. Bjerrum and NGI contribute to theoretical development, reliable analysis methods for soil and foundation behaviour, and instrumentation and measurement techniques to monitor and to verify analysis and design and foundation behaviour.
• NGI's first commercial assignment was assistance in the design of a new subway tunnel and the Grønland station in the centre of Oslo.
• Quick clay slides at Bekkelaget and Ullensaker leads to an increased focus on quick clay research and mapping of slide prone areas.
• NGI Publication series is established, presenting results from NGI's research activities.
• NGI develops new equipment to measure pressure and deformations in the ground, based on the vibrating wire principle. 

1960

• NGI becomes an important contributor in the design of the many embankment dam projects in Norway. NGI especially contributes to the selection of suitable building materials and construction methods and to evaluate stability and design. Alternative dam sites are examined; projects are administered and on going projects are being monitored.
• As a security against bottom heave and undesirable deformations when building tunnels in soft clay, an innovative solution is developed based on the use of cross braced slurry walls under terrain.
• Much effort was put into the analysis of ultimate shear strength of soft marine clay. In conjunction with this, large scale test equipment to perform direct shear experiments was developed.
• NGI is responsible for the construction of a combined tunnel for the Oslo subway and the railroad system through down town Oslo, where a 15 m deep excavation in soft clay was required.
• NGI performs extensive research with field vane sounding to determine shear strength of clay.
• NGI develops DSS-equipment (Direct Simple Shear).
• NGI hosts the International Geotechnical Conference.
• NGI starts using the element method (FEM) for geotechnical analysis.

1970

• The Norwegian oil age begins. NGI was soon involved with soil investigations for field developments and various foundation solutions for offshore structures. The new concept of gravity base structures (GBS) was developed and acquired by the oil companies. In all ten concrete GBS platforms, named Condeep, were built and installed in the North Sea.
• Extensive laboratory testing studied the effect of the cyclic load on the strength and stiffness in sand and clay.
• NGI starts research on avalanche danger on the new research station, Fonnbu in Stryn. Since then NGI has mapped over a thousand different avalanches in Norway.
• NGI continuously works to develop new offshore concepts and foundation solutions due to handling of more extreme conditions (larger waves and areas with greater water depth).
• The Q-method is developed at NGI, a system to classify rock mass stability and to decide required bolting and other means of securing tunnel safety. The method is today used worldwide.
• The quick clay slide in Rissa in April 1978 contributes to an extensive mapping of quick clay areas in Norway.

1980

• NGI receives an award from ASTM for a paper on 'Triaxial testing at NGI'.
• An increased focus on ground contamination results in NGI's first significant job in environmental geotechnics at the Norsk Hydro plant facility at Hærøya. New expertise and competence is developed in the field.
• Research on clay shale and chalk in offshore oil and gas reservoirs contributed to reduced cost in drilling of wells, and to enhanced oil and gas recovery.
• Research on new methods for determination of soil strength and behaviour results in refined geotechnical analysis and design.
• A georadar is developed at NGI.
• The Gullfaks C platform is installed.
• NGI participates actively in the foundation engineering of the Hibernia platform in Arctic waters offshore Canada.
• NGI intensifies its activity in the field of petroleum reservoir mechanics.
• Pile tests in Onsøy, Lierstranda and Shropshire (UK) are conducted.
• A tragic avalanche accident takes place in Vassdalen in northern Norway during the annual NATO winter training. 16 soldiers are killed as the avalanche hits the group.
• NGI participates actively in instrumentation of bridges
• Fjellinjen, a road tunnel through the centre of Oslo, is built with assistance from NGI.

1990

• The Snorre tension leg platform with suction anchors is installed in the North Sea. 
• The suction anchor, a new mooring concept for oil platforms is developed. Since then NGI has installed over 150 platforms with this mooring solution worldwide.
• NGI's competence in geomechanics is employed to evaluate the effects of earthquakes, blasting and ground shocks in relation to vibration from industry, construction and heavy transportation.
• Methods for mapping oil reservoirs through electromagnetic methods are developed, both to find new reservoirs and to monitor existing ones.
• The Troll A platform is installed. Today it is still the world's largest GBS.
• NGI provides expert assistance in the construction of a subway tunnel in Taipei, Taiwan.
• Two books are published at NGI: Rockfill Dams and Asphaltic Concrete Cores for Embankment Dams.
• NGI conducts soil investigations for the new Oslo airport at Gardermoen, the most extensive onshore site investigation in Norway to date.
• During the 1990s NGI increases its involvement in R&D projects funded by the European Union.
• NGI is certified according to ISO-9000.
• Suction anchors installed offshore several countries in Africa.
• Extensive NGI involvement in development of fields offshore Brazil.
• The Laerdal road tunnel, the world's longest road tunnel, is constructed with NGI assistance.
• NGI conducts soil investigations for an aluminium factory in Trinidad.

2000

• Comprehensive geohazard studies are conducted at the site of the historic Storegga landslide for the development of the Ormen Lange gas field in the Norwegian Sea.
• Further development of the use of electromagnetic waves for oil and gas exploration. One of the results of this project is the establishment of EMGS AS, where NGI had a small ownership.
• Because of several earthquakes and hurricanes that has caused heavy rainfall and flooding, NGI conducts risk evaluations for landslides in El Salvador and other Central American countries. 
• NGI develops a new seabed shear wave seismic source as a complementary tool for traditional geophysical mapping.
• NGI conducts risk evaluations in Southeast Asia after the tsunami tragedy that was triggered by an earthquake in the Indian Ocean the 26th of December 2004. 
• Through the Norwegian Ministry of Foreign Affairs, NGI starts cooperating with several Indian R&D institutes.
• A new Opera is built in Oslo; NGI is responsible for parts of the foundation design of for handling of the contaminated seabed sediments at the site.
• The Shah Deniz platform is installed in the Caspian Sea.
• NGI provides assistance after a severe earthquake in Pakistan 
• A deep sea disposal site for contaminated sediments from the Oslo harbour is established at the nearby site Malmøykalven.
• NGI plans and has engineering designs for the new under water road tunnel that will cross the Bjørvika in Oslo harbour, next to the new Oslo Opera House.
• NGI conducts geohazards evaluations in the Indian Ocean on behalf of the Indian Oil company Reliance.
• The Åknes / Tafjord project is started, for the evaluation of landslide and tsunami risk.
• Optical fibres are installed on the Göta river Bridge structure in Gothenburg to monitor the bridge integrity and safety during operation.