During the oil boom period, the world oil market was under the control of OPEC and this almost omnipotent organization was generally able to determine oil prices at will. OPEC members took it for granted that oil-consuming countries should pay high prices by adding premiums and surcharges on their crude oils without any consideration of economic logic particularly in the late 1970s and early 1980s. They seemed to be acting as if this tight market situation would continue for a long time and their predominant power in the world oil market would be perpetuated. In this period, Saudi Arabia tried to prevent oil prices from skyrocketing by producing its oil at maximum capacity, because the long-term economic and political interests of the Kingdom were embedded in moderate oil prices unlike other OPEC members. As David Golub and William Quandt argues, there were some exceptional cases in Saudi oil policy during political emergencies, however, Saudi Arabia generally pursued moderate oil prices by increasing production under tight market conditions. World oil market situation changed in the 1980s. Oil demand dropped and non-OPEC output increased continuously at the expense of OPEC’s market share. As the oil-consuming countries prepared for stockpiling as a useful means against a possible supply disruption or skyrocketing oil price after the 1973-74 oil embargo, they could effectively increase their bargaining power vis-à-vis OPEC members through the mechanism of stockpiling and destocking in accordance with the market situation. Furthermore, market forces began to have an increasing influence in the oil market during this period. All these changes challenged OPEC’s predominant position by undermining OPEC’s price structure and asked Saudi Arabia to have different tasks within OPEC. Previous studies regarding Saudi oil policy were basically constructed on tight market conditions without the consideration of structural changes in the world oil market during the 1980s. They failed to explain why Saudi Arabia played a swing producer role in the first half of the 1980s and gave up this role in 1985. In a slack market situation, Saudi Arabia should cut production to prevent oil prices from collapsing. Changing market situations require Saudi Arabia to modify its oil policy with different solutions. In my research, I will demonstrate how the structural changes of the world oil market in the 1980s readjusted Saudi oil policy and what were major factors for the success of Saudi oil policy by primarily using Petroleum Intelligence Weekly.