["International Journal of Urban and Regional Research, EarlyView. ", "\nAbstract\nThis article analyzes why the San Diego‐Tijuana city system has undergone a process of supply chain urbanism—development in the logistics sector—since 2013. The article compares the 2003–2013 period, during which the region saw a lack of growth in the transportation and warehousing sector, with the 2013–2023 period, when the sector underwent regionally specific growth at unprecedented rates, measured through increases in employment and cross‐border commercial traffic. It is argued that changes in trade law and trade relations, global/transpacific supply chain contingencies, and transnational planning and infrastructure investments have led to supply chain urbanism in San Diego‐Tijuana. Due to contingencies in transpacific supply chains, it is argued that the region has developed a new logic of warehousing, moving from a just‐in‐time model to a just‐in‐case model. Lastly, the article comments on the effects of supply chain urbanism in the region.\n"]