1925
• Two-year exploration licence granted to D’Arcy Exploration Company.

1937
• Concession covering the territories of Oman and Dhofar awarded to Iraq Petroleum Company (IPC), later transferred to Petroleum Development (Oman and Dhofar) Ltd.
1951
• Dhofar relinquished from the concession portfolio; thereafter, company name Petroleum Development (Oman) adopted.
1952
• Dhofar Concession acquired by Dhofar-Cities Service.
1954
• Petroleum Development (Oman) Ltd establishes base at Duqm and makes first geological survey at Fahud.
1956 - 1960
• Exploration wells drilled at Fahud, Ghaba, Haima and Afar without finding oil in commercial quantities.
1957
• Dhofar-Cities Service discovers oil at Marmul, but find is judged to be uneconomic to develop.
1960
• Most IPC partners in Petroleum Development (Oman) withdraw from venture, leaving Oman concession to Royal Dutch/Shell Group and Partex.
1962
• Oil is struck at Yibal and Natih. Dhofar concession surrendered.
1964
• Oil discovery made at Fahud. Decision is taken to develop and export oil from Yibal, Natih and Fahud.
1967
• Oil exports start on July 27. Compagnie Française des Pétroles takes over two-thirds of Partex’s equity share in Petroleum Development (Oman), resulting in the following shareholding: Shell 85 per cent, Compagnie Française des Pétroles 10 per cent and Partex five per cent.
1969
• Dhofar regained as part of Petroleum Development (Oman) concession area. Discovery at al-Huwaisah.
• Oil production: 327,000 bpd.
• Oil reserves: 1.46 billion barrels.
1970
• Sultan Qaboos bin Said comes to power.
• Oil production: 332,000 bpd.
• Oil reserves: 1.74 billion barrels.
1972 - 1973
• Discoveries in central Oman – Qarn Alam, Ghaba North, Saih Nihayda, Habur and Saih Rawl.
• Oil production: 281,778 bpd.
• Oil reserves: 1.64 billion barrels.
1974
• Government acquires 25 per cent stake in concession in January, increased retroactively in July of that year to 60 per cent. Private shareholders now consist of Shell (34 per cent), Compagnie Française des Pétroles (four per cent) and Partex (two per cent).
• Oil production: 290,770 bpd.
• Oil reserves: 1.49 billion barrels.
1975-1976
• Central Oman oilfields brought onstream.
• Oil production: 280,330 bpd.
• Oil reserves: 1.28 billion barrels.
1977
• The Government and private shareholders signed a new long-term agreement providing for the development of the south Oman oilfields. Discovery at Rahab.
• Oil production: 340,160 bpd.
• Oil reserves: 1.38 million barrels.
1978
• Discoveries at Birba, Qaharir, Mahjour, Rima, Jalmud, Runib, Qata, Dhahaban South, Nimr, Jazal, Zauliyah North East, Sayyala, Suwaihat, Karim West, Nimr West, Wafra, Fayyadh, Amin, Dhulaima, Kaukab, Bahja, Jawdah, Hasirah, Anzauz, Burhaan, Ihsan and Jameel.
• Oil production: 314,333 bpd.
• Oil reserves: 1.50 billion barrels.
1979
• Discovery at Rima. Natural Gas Liquids Plant commissioned at Yibal.
• Oil production: 295,000 bpd.
• Oil reserves: 2.48 billion barrels.
1980
• Company locally registered as limited liability company by Royal Decree under the name Petroleum Development Oman. Southern oilfields brought onstream. Discovery at Nimr.
• Oil production: 282,000 bpd.
• Oil reserves: 2.48 billion barrels.
1981
• Marmul and Qaharir fields brought onstream.
• Oil production: 317,000 bpd.
• Oil reserves: 2.90 billion barrels.
1982
• Discoveries at Sayyala and Suwaihat. Rima brought onstream.
• Oil production: 324,500 bpd.
• Oil reserves: 2.98 billion barrels.
1983
• Discoveries at Wafra and Fayyadh. Gas found to the south of Jabel Salakh at Habiba and Rasafah. The Saih Nahayda gas treatment plant came onstream.
• Oil production: 376,551 bpd.
• Oil reserves: 3.46 billion barrels.
1984
• Major new Agreement signed between the Government and PDO for 10-year exploration programme to search for new reserves of natural gas.
• Oil production: 407,000 bpd.
• Oil reserves: 3.84 billion barrels.
1985
• Sultan Qaboos bin Said opened Marmul Pilot Steam Plant. Discoveries at al- Dhabi, Dhiab, Maqhoul South (gas), Yibal deep, Zareef, Hasirah, Mawhoob, Mukhaizna, Simsim, Taf Dahm (gas), Thuleilat and Warad.
• Oil production: 489,000 bpd.
• Oil reserves: 4.00 billion barrels.
1986
• Nimr Production Centre opened. Discoveries at Yibal Deep, Lekhwair Deep, Lekhwair East, Hadh, Saih Rawl South, Sadad, Reihan, Salwa and Zahra. Seven new fields brought onstream: Barik, Fayyadh, Zareef, Jalmud, Jalmud North, Jawdah and Runib.
• Oil production: 551,184 bpd.
• Oil reserves: 3.96 billion barrels.
• Gas reserves: 9.3 trillion cu ft.
1987
• Sultan Qaboos bin Said visited Sayyala Production Station.
• Significant discoveries in Khuff reservoirs of Yibal, al-Huwaisah, Alam, Sadad, Thamoud and al-Burj. Eleven new fields brought onstream: Hasirah, Warad, Simsim, Zahra, Ihsan, Jameel, Mawhoob, Dhiab, Thuleilat, Yibal Khuff and Al-Burj.
• Oil Production: 571,000 bpd.
• Oil reserves: 4.08 billion barrels.
• Gas reserves: 9.3 trillion cu ft.
1988
• The 50th oilfield brought into production. Bahja permanent production station commissioned and a new gathering station commissioned in the Yibal field. Four new fields brought onstream: Rajaa, Zumurrud, Reihan and Ramlat Rawl.
• Oil production: 601,000 bpd.
• Oil reserves: 4.11 billion barrels.
• Gas supplied: 4.3 million cubic metres/day.
• Gas reserves: 9.3 trillion cu ft.
1989
• Six new fields brought onstream: Thayfut, Alam, Qarat al-Milh, Haima, Thamoud and al-Dhabi. First reserves booking of non-associated gas and condensate in the Saih Nihayda field.
• Oil production: 616,000 bpd.
• Oil reserves: 4.16 billion barrels.
• Gas supplied: 4.5 million cubic metres/day.
• Gas reserves: 9.8 trillion cu ft.
1990
• Three new fields brought onstream: Amin, Sadad and Wadi Haka.
• Oil production: 652,000 bpd.
• Oil reserves: 4.25 billion barrels.
• Gas supplied: 4.8 million cubic metres/day.
• Gas reserves: 9.9 trillion cu ft.
1991
• First offshore well drilled in Sawqrah Bay, 300 km from Salalah; however, no oil was found, and the was well plugged and abandoned. Five new fields brought onstream: Basma, Jadeer, Yasmeen, Ghazar and Arnab. Major gas discoveries at Saih Rawl and Barik in central Oman.
• Oil production: 665,000 bpd.
• Oil reserves: 4.35 billion barrels.
• Gas supplied: 5.0 million cubic metres/day.
• Gas reserves: 12.3 trillion cuft.
1992
• Two new fields brought onstream: Al-Rodha and Hazar. The new Lekhwair Production Station began operations.
• Oil production: 692,000 bpd.
• Oil reserves: 4.60 billion barrels.
• Gas supplied: 5.5 million cubic metres/day.
• Gas reserves: 16.8 trillion cuft.
1993
• Production reached record levels. Extensive seismic survey completed throughout Salalah. North Oman Crude Stabilisation project started, to improve recovery of natural gas. High-pressure gas injection production facility at Birba came onstream. Non-associated gas reserves deemed sufficient to supply a LNG export scheme.
• Oil production: 733,000 bpd.
• Oil reserves: 4.83 billion barrels.
• Gas supplied: 6.1 million cubic metres/day.
• Gas reserves: 20.9 trillion cu ft.
1994
• Yibal Butane Project finished. Plans for supply of gas to LLNG Project completed. First carbonate-stringer reserves booked, amounting to 95 million barrels.
• Oil Production: 761,000 bpd.
• Oil reserves: 5.04 billion barrels.
• Gas supplied: 6.9 million cubic metres/day.
• Gas reserves: 25.3 trillion cu ft.
1995
• Gas export facilities installed at Anzouz.
• Oil Production: 803,000 bpd.
• Oil reserves: 5.11 billion barrels.
• Gas supplied: 6.5 million cubic metres/day.
• Gas reserves: 27.5 trillion cu ft
1996
• PDO concluded an agreement with the Government for the development of the central Oman gasfields. Construction began of Saih Rawl Central Gas Treatment Plant and the Gas Pipeline to the LNG Plant at Qalhat.
• Oil production: 830,000 bpd.
• Oil reserves: 5.14 billion barrels.
• Gas supplied: 6.6 million cubic metres/day.
• Gas reserves: 28.3 trillion cu ft.
1997
• Major ‘new oil’ credited to Al-Shomou and the Harweel Deep carbonate stringers near Birba.
• Oil production: 846,000 bpd.
• Oil reserves: 5.28 billion barrels.
• Gas supplied: 7.3 billion cubic metres/day.
• Gas reserves: 28.5 trillion cu ft.
1998
• Cost reductions implemented as a consequence of historically low oil prices. Another carbonate stringer field – Sarmad – discovered. Maurid, Maurid NE, Wazar, Arnab and Tuqaa fields brought onstream.
• Oil production: 835,000 bpd.
• Oil reserves: 5.38 billion barrels.
• Gas supplied: 8.1 million cubic metres/day.
• Gas reserves: 29.1 trillion cu ft.
1999
• Upstream LNG project completed. PDO becomes the first exploration and production company in the Middle East – and one of the very few E&P Companies in the world – to be awarded an ISO 14001 certificate for the entirety of its operations. Year finished without a work-related fatality. Ghafeer field, with 60 million barrels of booked oil reserves, discovered.
• Oil production: 832,000 bpd.
• Oil reserves: 5.51 billion barrels.
• Gas supplied: 8.5 million cubic metres/day.
• Gas reserves: 29.3 trillion cu ft.
2000
• Sakhiya field discovered. Al Noor, Mukhaizna and Burhaan come onstream. Oman’s first planetarium opened to the public as a “Gift to the Nation” from PDO. Permanent accommodation centres opened at Fahud and Nimr, significantly improving living conditions of PDO’s contractor staff.
• Oil production: 840,000 bpd.
• Oil reserves: 5.62 billion barrels.
• Gas supplied: 19.7 million cubic metres/day.
• Gas reserves: 30.3 trillion cu ft.
2001
• PDO maintains its proud record of supplying 100 per cent of the gas demanded by its customers. The Kauther gasfield is discovered. PDO opens a virtual reality centre enabling three-dimensional models of underground rock formations to be viewed from all angles. The Company’s Learning and Development Centre is awarded ISO 9001 Certification.
• Oil production: 831,000 bpd
• Oil reserves: 4.86 billion barrels    
• Gas supplied: 34.3 million cubic metres / day    
• Gas reserves: 33.4 trillion cu ft (associated and non-associated)
2002
• PDO opens its Business Development Centre which is intended to encourage local businesses and community-based contractors. The company reorganised and the hydrocarbon producing assets were merged into two major operating units – North and South- each led by a director.
• Oil production: 771,000 bpd.
• Oil reserves: 5.35 billion barrels.
• Gas supplied: 37.4 million cubic metres/day.
• Gas reserves: 34.24 trillion cu ft.
2003
• PDO celebrated 25 years of providing an uninterrupted supply of gas to the nation. A study centre was established to deepen the company’s understanding of its reservoirs. Sixty local community contractors were awarded contracts worth more than RO 15 million.
• Oil production: 702,000 bpd.
• Oil reserves: 5.2 billion barrels.
• Gas supplied: 40.2 million cubic metres/day.
• Gas reserves: 34.5 trillion cu ft.
• Statistics according to the Ministry of Oil and Gas annual statistics.
2004
• A new directorate was established specifically to plan and carry out enhanced oil recovery projects. First oil was produced from the Harweel cluster of fields and approval was given to carry out enhanced oil recovery (EOR) projects.
• Oil production: 661,000 bpd.
• Gas supplied: 38.7 million cubic meters /day.
 2005:
• Four oil fields discovered; two in the North (at Ufuq and Dafiq) and another two in the South (at Sakhiya-Southwest and Mamour).
• The Saih Nihayda Gas Plant (SNGP) began supplying gas to the Oman Liquefied Natural Gas plant near Sur in March 2005 and gas from SNGP was delivered to the just-opened Qalhat Liquefied Natural Gas plant, also located near Sur, through a new 48-inch pipeline that was designed and laid by PDO.
• Working alongside the Royal Oman Police, Oman’s first-ever Traffic Safety Institute was established as a ‘Gift to the Nation’ to mark the Sultanate’s 35th National Day. The company’s approach to contracting and procurement has radically changed in close consultation with the Government and the Company’s providers of goods and services.
• Oil production: 631,000 bpd
• Gas supplied: 49.7 million cubic metres/day.
 2006
• First-of its-kind service contract signed for the development of PDO’s Karim small-field cluster, which gives the contractor company Medco Energi effective control of the field’s operations while retaining ownership of them and their reserves with PDO.