In 1934, Dr. Louis Dame, an American medical missionary working on behalf of the Reformed Church of America’s “Arabian Mission,” paid a visit to the Sheikh of Qatar. Although Dame’s trip was primarily to provide medical services on behalf of his mission, American representatives from Standard Oil of California (SOCAL) had also secretly tasked him with assessing whether the Qatari Sheikh would be interested in signing a new concession with Americans after their current concession agreement with the British expired. American oil developers had already benefited from the missionaries’ wide network of contacts and positive relationships with local Arab rulers, including the King of Saudi Arabia, Ibn Saud, with whom SOCAL had just signed a concession. RCA missionaries had been offering their medical services to Ibn Saud and his family for the last two decades. Medicine, the missionaries maintained, had served as an “opening wedge” providing them access into these rulers’ homes. American oil executives were well aware of this fact. Two years after Dame’s visit to Qatar, they invited him to come work for the company that would later be known as ARAMCO. Cooperation would not end there. In the following years, American missionaries continued to work closely with ARAMCO as the company developed its medical facilities and schools in Saudi Arabia. When ARAMCO created the Arabian Research Division, a department whose “chief function” was to gather information about Arabian history and Islam in order to “know and understand the Arab,” missionaries would play a key role in training the division’s employees. Although ARAMCO executives and American missionaries had differing objectives in the area, both believed that modernization and development were essential to their ultimate goals. This paper will analyze how these two groups cooperated on the ground and how such cooperation shaped early modernization narratives about Saudi Arabia in the period between 1933 and 1955.