"A project to build a Nordic Telescope was first proposed in 1980 by Profs. Bengt Strömgren and Anders Reiz, who obtained funding for a feasibility study for a 2.5m telescope from the Carlsberg foundation. A feasibility study by Torben Andersen was completed in July 1981 and discussed at the Nordic Astronomy Meetings in November 1981 and February 1982. A Nordic Optical Telescope Committee was formed in September 1982 and a revised project study was presented at the end of 1982. Funding for initial project activities, notably site testing and progress on detailed design, was provided in early 1983 by the Swedish and Danish Natural Science Research Councils.
The project became reality in December 1983, when the Nordic Council of Ministers allocated 8 MSEK to the construction, upon which the four Nordic research councils (Denmark, Finland, Norway, and Sweden) approved the remaining 21 MSEK. Thus, the Nordic Optical Telescope Scientific Association (NOTSA) was founded in January 1984, and the first Council and Director (Arne Ardeberg, Lund) were appointed (Iceland joined NOTSA later, in 1997).

Substantial work started in July 1984, when a technical project group was formed, and the main design features of the NOT were approved in early 1985. At the same time, it was decided to locate the telescope at the new observatory site on La Palma. After a number of technical and financial difficulties had been overcome, the NOT was inaugurated in 1989, and regular observations started in 1990. The initial years of operation proved the excellent basic qualities of the telescope and the site but, as pointed out by an international review panel in 1994, deficiencies in the instrumentation and insufficient staff for the operations on La Palma still prevented the telescope from reaching its full potential.

Under Vilppu Piirola (Turku), who took over as Director in 1995, the budget and operations of NOTSA were thoroughly reorganised with a focus on the scientific output. An adequate scientific and technical staff on La Palma was recruited, headed by an experienced Astronomer-in-Charge, Hugo Schwarz, and an ambitious, systematic programme brought the NOT operations up to international standards. At the same time, the Associates funded a joint programme to equip the telescope with a versatile set of state-of-the-art optical and near-infrared workhorse instruments. As a result, the scientific interest in and reputation of the NOT increased steadily, as reflected in the annual lists of publications based on NOT data. A far-sighted step in this period was to join the EU-funded Infrastructure Coordination Network OPTICON, which involved the NOT - and Nordic astronomy in general - in the initiatives to promote greater synergy and coordination in European ground-based astronomy.

The NOT was thus already a well-established, successful operation in 2002, when Johannes Andersen and Thomas Augusteijn became Director and Astronomer-in-Charge (later Deputy Director). Gradual instrumentation upgrades continued (new detectors; a stable location for the high-resolution spectrograph FIES), and financial reserves also made it possible to overhaul and completely renew the telescope control and cooling systems, securing continued operation for another couple of decades. In parallel, a sustained programme was pursued to document and streamline telescope, instrument and data flow operations so as to improve the efficiency, flexibility and reliability of the operations and the short- and long-term scientific value of the data. Notable scientific results include long-term monitoring of active stars and rapid response to events in the emerging fields of Gamma-Ray Bursts and exoplanets (for more detail, see the Annual Reports and lists of publications). A programme of training activities, including an expanded Research Student programme, was also developed. At the end of September 2013 Johannes Andersen retired, and Thomas Augusteijn was appointed Director as of October 1st, 2013."