In December 1969, President Chujiro Fujino signed a joint venture agreement establishing Brunei LNG. The agreement called for Shell and Mitsubishi Shoji to each take a 45% stake in the venture, with the Brunei government holding a 10% interest. It was an extremely weighty decision as the amount of investment required for participation in the massive project was $125 million, a figure which far exceeded Mitsubishi Shoji's capital at the time. If the project failed, the fallout would be so great that "it could bring down Mitsubishi Shoji three times over". In an era when there was very little foreign investment by Japan's sogo shosha, the project marked the start of a new chapter in the company's history.

In the 1960s, demand for large quantities of raw materials emerged as Japan entered a period of high growth and as heavy and chemical industries began to flourish. Containing almost no sulfur content and no carbon monoxide, natural gas represented a clean source of energy with a high heating value and Mitsubishi Shoji was quick to focus on liquefaction as a means of transporting natural gas to Japan. In 1968, Shell approached Mitsubishi Shoji about joint investment in LNG development in Brunei. The joint venture agreement was concluded following exhaustive investigations by the project team at Mitsubishi Shoji. The zeal and hard work of the project team came to fruition in December 1972, when the first ship carrying LNG from Brunei arrived in Osaka.

Under President Fujino, Mitsubishi Shoji became involved in a string of large projects overseas and was especially active in securing participation in resource development projects. Around this time, there was an increase in development-oriented loan and investment projects, with an eye toward securing natural resources, and long-term, large-scale import agreements. Examples include projects related to iron ore and coal in Australia, copper in Zambia and wood pulp in Canada. In this way, Mitsubishi Shoji came to play a major role in procuring resources for Japan.

During the tenure of President Fujino, Mitsubishi Shoji not only expanded business globally, but it also promoted the shift from simple trading to development and investment, thereby spurring the evolution of the business model that characterizes today's MC Group. In 1971, the company adopted the English name of Mitsubishi Corporation.