In much of Eastern Africa, the last decade has seen a renewed interest in spatial development plans that link mineral exploitation, transport infrastructure and agricultural commercialisation. While these development corridors have yielded complex resultseven in cases where significant investments are yet to happenmuch of the existing analysis continues to focus on economic and implementation questions, where failures are attributed to inappropriate incentives or lack of 'political will'. Taking a differentpolitical economyapproach, this article examines what actually happens when corridors 'hit the ground', with a specific interest to the diverse agricultural commercialisation pathways that they induce. Specifically, the article introduces and analyses four corridors-LAPSSET in Kenya, Beira and Nacala in Mozambique, and SAGCOT in Tanzaniawhich are generating 'demonstration fields', economies of anticipation and fields of political contestations respectively, and as a result, creatingor promising to creatediverse pathways for agricultural commercialisation, accumulation and differentiation. In sum, the article shows how top-down grandmodernist plans are shaped by local dynamics, in a process that results in the transformation of corridors, from exclusivist 'tunnel' visions, to more networked corridors embedded in local economies, and shaped by the realities of rural Eastern Africa.