This Chapter explores the evolution of regional development in China’s less developed areas, focusing on spatial and temporal patterns. It reviews historical strategies such as the prioritization of the eastern seaboard, the Western Development Strategy, and the rise of central China, addressing regional disparities. Key drivers include rapid economic growth, urbanization, ecological civilization, and social improvements. The chapter analyzes economic and ecological efficiency, highlighting their roles in sustainable development. Finally, it examines social development and anti-poverty measures, using empirical models to identify influencing factors. The chapter provides a concise overview of the challenges and achievements in balancing regional development in China. The objectives of this chapter are as follows: 1. To examine the economic disparities between developed and less developed regions, analyze the main factors contributing to these imbalances, and explore the drivers of regional development, such as industrial structure, technological progress, and levels of informatization. 2. To analyze the spatial and temporal patterns of regional development during the process of rapid urbanization, study the impact of urbanization on economic growth, resource allocation, and the ecological environment, and evaluate urbanization’s role in promoting regional development. 3. To evaluate the ecological efficiency of different regions, study the role of sustainable development policies and measures in promoting the balance between economic growth and ecological conservation, and explore pathways to achieve high-quality development. 4. To investigate the main drivers of regional development, including economic growth, industrial transformation, ecological civilization construction, and social and livelihood improvements, and analyze how these factors collectively promote the development of less developed regions.