Economic regionalism and free trade are key drivers of global economic growth, integration, and stability. Regional economic integration aims to enhance efficiency through larger markets, economies of scale, and reduced transaction costs, thereby enabling more effective responses to global shocks. The staged model of building integration, as suggested by Bella Balassa, which ranges from preferential trade agreements and regional trade areas (RTAs) to customs unions, single markets, and full economic and political unions, offers a valid explanation for the evolution of key integration entities in Eurasia. While integration promotes trade, investment, and institutional cooperation, critics argue it can lead to trade diversion and undermine multilateralism under the WTO. Debates focus on whether RTAs are building blocks or stumbling blocks to global liberalization. Even if evidence suggests that trade creation and economic dynamism prevail, political considerations, migration, and demographic shifts negatively affect trade policies today. “Deep integration” trends and mega-regional agreements have subsided, with some notable exceptions, such as the EU. Integration challenges include unequal development within regional integration entities and between regions, political resistance, and crises that test regional solidarity. Still, well-designed regional policies can support good governance and sustainable and inclusive economic growth. Regionalism complements multilateralism when structured to ensure mutual benefits and adaptability in a shifting global landscape.