Development corridors are linear programmes of infrastructure and agriculture aiming to facilitate rapid socio-economic development. In Africa, they are a major development activity, with 88 underway or planned corridors. Drawing from extensive literature and insights gleaned from a 4 year research programme, this review scrutinizes the impacts of development corridors on people, wildlife and ecosystems in Kenya and Tanzania, proposing solutions to achieve better outcomes. The overarching goal was to discern the principle challenges emerging from the practical execution of the prevailing corridor model. The holistic approach taken, assessing the development corridors paradigm through an integrated ecological, social, and economic lens, provides novel insights that have not been possible using more traditional—siloed—research approaches. Eight key challenge areas are identified: impact assessments processes; coherence across international, national and local planning; governance; inclusivity; equality; impacts on biodiversity and ecosystem services; incorporation of future climate risks; and integrated water resource management. Poorly planned and implemented corridors detrimentally impact livelihoods and ecosystems. They lack a sustainable development vision, detailed social, environmental or climate risk assessments, and develop incrementally in policy and corporate spaces. There is also often a disconnect between investors and recipient governments, with some investors funding what governments request without applying internationally-recognised safeguards, and governments lacking capacity and resources to enforce regulations. We make recommendations for addressing these challenge areas. These aim to enhance impact assessment efficacy; integrate local perspectives into effective and inclusive corridor planning; overcome siloed project development and implementation; anticipate future development projections; and prioritise landscape preservation for enhanced ecosystem services and climate resilience.