Professor Hua Loo-Keng is the first person to have undertaken the task of popularizing mathematical methods in China. As early as 1958, he proposed that the application of operations research methods be initiated in industrial production. With his students, Yu Ming-I, Wan Zhe Xian and Wang Yuan, Professor Hua visited various transportation departments to promote mathematical methods for dealing with transportation problems, and a mass campaign was organized by them and other mathematicians to advance and apply linear programming methods to industrial production in Beijing and in Shandong province. However, due to the fact that these methods have limited applications and their computation is rather complex, their popularization and utilization in China have so far been restricted to a small number of sectors such as the above mentioned transportation departments. In 1958 Hua Loo--Keng proposed the use of Input-Output methods in the formulation of national economic plans. Apart from publicizing this method, he carried out in-depth research on the subject. He also gave lectures on related non-negative matrix theory, pointing out the economic significance of various theoretical results.