Morris has also made remarkable achievements in economic growth and development. He co-edited the book "Economic Growth Model" with Stern, and the book "Project Signing and Planning in Developing Countries" was published in Little, and the article "Pure Theory of Studying Underdeveloped Economy by Using the Relationship between Consumption and Productivity" was published in 1975, which used economic policies, especially growth theory.
This paper discusses the influence of uncertainty on moderate growth, the theory of non-renewable resources, the theory of indivisible growth and the irreplaceable theorem of durable goods. In the field of economic development, Morris put forward a cost-benefit analysis method, established a low-income economic development model, and studied the effectiveness and results of international aid policies. Morris visited China on 1998.