Toward Climate-Resilient Agribusiness and Food Security in Kenya’s Highland Counties: Evidence from Kisii and Nyamira Counties

Climate variability increasingly threatens the sustainability of smallholder agriculture and food systems in Kenya, particularly in the densely cultivated highlands of Kisii and Nyamira counties. This study examined climatic vulnerabilities, agribusiness adaptation strategies, institutional responses and their implications for building sustainable food systems in the two counties. A systematic literature review, guided by PRISMA principles, was undertaken using 62 publications drawn from peer-reviewed literature, policy documents and institutional reports published between 2015 and 2026. The evidence was analysed through thematic synthesis. Findings indicate that agribusiness systems in Kisii and Nyamira are increasingly exposed to rainfall variability, soil degradation, water stress, changing pest and disease dynamics, and land fragmentation. Smallholder farmers respond through crop diversification, intercropping, livestock integration, soil and water conservation, organic soil management and other climate-smart agricultural practices. However, the effectiveness and wider adoption of these strategies are constrained by limited finance, uneven extension services, inadequate infrastructure, restricted access to climate information and inequalities in productive resources. The study argues that climate resilience cannot be secured through isolated farm-level interventions. Rather, sustainable food systems require an integrated agribusiness approach linking climate-smart production with markets, finance, climate information, infrastructure and responsive institutions. Strengthening these interconnections is critical to sustaining productivity, livelihoods and food security in the Kisii–Nyamira highlands.