Toyota Motor Co., Ltd. started at the beginning of 1949 a preliminary investigation for statistical quality control with the Machining Plant as a model factory. The following year, the company moved into more proper study in January 1950 and quality control of machining parts was begun.

The Inspection Division and the Machining Division were in charge of quality control work, and a statistical quality control technique was applied to the essential operations. P-charts were used for material defects of machine shop parts, and if the control limits were exceeded the raw blank divisions were contacted and measures to prevent recurrence were taken. In the same way control charts were used for machining defects, and if a defect occurred, its cause was pursued and countermeasures were studied and implemented. When the control charts were first put up on the shop floor the reaction of the workers varied from complete indifference to resistance against being restricted or an excessive sense of nervousness. But through workshops and daily practice the role of control charts through statistics became recognized.

In May 1953 Director Shoichiro Toyoda took up the post of General Manager of the Inspection Division and worked to strengthen the quality control system. As a concrete measure the newly established Quality Control Sub-Section drew up a plan to implement quality control for the entire manufacturing process, and held workshops to disseminate this plan. In addition, in order to implement quality control in partner plants, the reasons for its introduction was explained at a general meeting of the Kyohokai, and a request was made for the suppliers' thoroughness and collaboration.

Then the Quality Management Committee and seven Specialist Committees were established. The Quality Management Committee planned and discussed matters relating to the entire system, such as the dissemination of quality control and education, while the Specialist Committees discussed and promoted matters relating to quality control in each manufacturing field. Internal entities and partner plants worked to promote these matters with an emphasis on quality control training.

In addition, inspection work that was undertaken by each plant amongst the various plants was centralized in the Inspection Division in 1954, and was changed into a system that could quickly take in information pertaining to quality for the whole company. In line with this, as the emphasis of the Inspection Division work moved to quality control, its name was changed to the Quality Control Division in June 1959.

Meanwhile, after the Motomachi Plant was completed in 1959, Toyota Motor Co., Ltd.'s production volume and number of employees increased rapidly, with a 6.7 fold increase in annual production volume in the years 1955 to 1960, from 21,909 units to 146,207 units, and a 1.9 fold increase in the number of employees from 5,162 to 9,950 people.1

With the rapid increase in production volume and the number of employees, less care was given to quality and staff training, and claim costs per vehicle-which had been continually decreasing-began to increase from 1959. Executive Vice President Eiji Toyoda, who was alarmed by this situation, presented his 'Requests regarding Inspection' in June 1960, after which the Quality Management Committee investigated potential measures. As a result it was decided in June 1961 to introduce Total Quality Control (TQC) for the managing of the company's business as a whole, using QC-like techniques.

Subsequently, the QC Promotion Group was set up in 1964, with Executive Vice President Eiji taking up the post of Chief Officer, and Managing Director Shoichiro and Managing Director Hanji Umehara the post of Deputy Chief Officers. Under this organization TQC was promoted company-wide, and the Deming Application Prize was awarded on October 11, 1965.