Recently, data released by Shanghai Customs shows that since the integration of the Yangtze River Delta region became a national strategy in 2018, the scale of foreign trade in the region has exceeded 100 trillion yuan. While achieving new heights in scale, the foreign trade structure of the Yangtze River Delta region continues to optimize, with the rise of "new three types" exports such as new energy vehicles, lithium batteries, and photovoltaic products, becoming a new engine for foreign trade growth. The resilience of foreign trade is an important component of China's economic development resilience and a crucial guarantee for achieving high-quality economic development. As the cornerstone of China's foreign trade, the Yangtze River Delta region has demonstrated strong development resilience and vitality, and has also provided useful references for the development of other regions. The integration and collaborative innovation of industries in urban agglomerations are one of the driving forces for the strong resilience of foreign trade development in the Yangtze River Delta region. The rapid development over the past 40 years has given rise to the autonomy and vitality of local governments. In the current domestic and international situation, Chinese cities' participation in global competition is at least based on regions rather than individual cities. Cooperation between cities is greater than competition. By forming complementary specialized division of labor networks between different cities within the same urban agglomeration, it can promote the flow of technological information and collaborative innovation in the industrial chain. It can also allocate resources on a wider scale, thereby gaining greater international competitive advantages. The development of the Yangtze River Delta urban agglomeration is exactly like this, which encourages effective market competition, pays more attention to preventing duplicate layout, encourages various regions to play to their comparative advantages, develop "long board" industries, and thus forms a regional specialized division of labor network, promotes integrated industrial layout, and expands new space for foreign economic and trade cooperation. The Yangtze River Delta urban agglomeration fully leverages the economies of scale advantages of agglomeration, while striving to alleviate the "big city disease" problem, and thus achieve the transformation of industries from scale and quantity to quality and efficiency at an earlier stage. As a space for social and economic activity aggregation, cities have significant economies of scale effects. With the expansion of urban scale, it is inevitable to encounter phenomena such as unreasonable spatial distribution and scale structure, uneven allocation of urban public services, and urban traffic congestion. This will reduce resource allocation efficiency, increase production costs for enterprises, and thus affect international competitiveness. As a cluster of cities, the concentrated distribution of cities within urban agglomerations can provide advantages in economies of scale; By rational industrial layout, it will effectively alleviate the traffic pressure and population density in central cities. That is to say, urban agglomerations allow cities that are clustered together to gain the advantage of agglomeration while avoiding the negative effects of their own expansion, while also taking into account regional coordinated development, resulting in a "1+1gt; 2" effect. This is also one of the reasons for the strong resilience of foreign trade development in the Yangtze River Delta region. In addition, the Yangtze River Delta region has taken the lead in launching and integrating multiple free trade pilot zones, becoming a "highland" for aligning with international high standard economic and trade rules. In recent years, the Yangtze River Delta urban agglomeration has actively carried out institutional innovation around the docking of international high standard economic and trade rules, relying on the platform of free trade pilot zones. These exploratory practices not only effectively reduce the costs of participating in international trade for enterprises in the region, including technical coordination costs, information communication costs, and compliance costs, but also promote the international flow and global exchange of innovation and service factors. These provide important guarantees for the development of new quality productivity in the Yangtze River Delta region, significantly enhancing the competitiveness of enterprises in the international market and promoting the prosperity and development of foreign trade in the region. Facing the future, the Yangtze River Delta urban agglomeration, which shoulders a new mission, should take advantage of the situation, continue to improve the regional coordination mechanism, promote industrial agglomeration and complementarity within the region, avoid "inward competition", and continue to promote the docking with international high standard economic and trade rules, injecting inexhaustible impetus into the development of regional foreign trade and helping to create a new pattern of higher-level reform and opening up. (Liao Xinshe) Author: Sun Puyang (Dean of China Institute of Economic Reform and Development, Renmin University of China, Professor of School of Economics)