Therefore, NOC is carrying out exploration and production operation through its own affiliated companies, or in participation with other companies under service contracts or any other kind of petroleum investment agreements . This is in addition to marketing operations of oil and gas, locally and abroad . For this purpose, NOC has its own fully owned companies which carry out exploration, development and production operations, in addition to local and international marketing companies. NOC also has participation agreements with specialized international companies. Such agreements have developed into exploration and production sharing agreements, in accordance with the development of the international oil and gas industry, and international petroleum marketing .

NOC owns refining, and oil and gas processing companies, operating refineriessuch as Zawia and Ras Lanuf refineries, ammonia, urea and methanol plants,  the Ras Lanuf petrochemical complex and the gas processing plan. To establish petrochemical industries, anther stage of development of the ethylene plant has been completed , as well as the low and high density linear polyethylene plants.

NOC also owns national service companies which carry out oil well drilling and work over operations, provide all drilling material and equipment, lay and maintain oil and gas pipelines, build and maintain oil and gas storage tanks and carry out related technical and economic studies . They also provide the sector with other services , such as catering, procurement of materials and equipment, training and employment of  foreign employees.

Also affiliated to NOC is a petroleum research centre which carries out research and technical studies related to the oil industry, conducts technical analysis and tests for the various stages of exploration and production of oil and petroleum products, performs quality control tests and issues certificates in this respect. It also evaluates patents and licenses of exploitation and the fees and forms related to oil operations and petroleum products . It publishes the studies carried out by the centre in the publication of the centre , as well as the local and international scientific publications.

In the area of manpower development, NOC provides the oil industry with qualified nationals within a well planned scheme founded on a base of educational and training institutions, for training and developing qualified manpower in such professions as engineering , accounting and administration.

Training outside the Great Jamahiriya is limited to those technical specializations which are not available locally, to cope with the rapid development of the industry. Technical training is being carried out at the training centers and institutions belonging to NOC, to develop specialized technicians for the operation and maintenance of industrial facilities and plants