Agricultural Extension and Rural Advisory Services: Theories, Approaches, Innovation Systems and Future Directions

Agricultural extension and rural advisory services are being asked to support productivity, climate adaptation, ecological stewardship and inclusive rural livelihoods under increasingly pluralistic and digitised arrangements. This critical narrative review evaluates how institutional design, farmer learning, digital tools and public accountability shape the prospects of such services. Peer-reviewed studies and selected authoritative evidence published from 2000 to 18 August 2026 were identified through accessible scholarly indexes, regional sources and citation tracking; seminal earlier ideas were considered where necessary. Evidence was appraised for causal identification, contextual transferability, service quality, equity and temporal durability rather than pooled into a single effect estimate. Randomised and quasi-experimental studies demonstrate that certain information and social-learning interventions can change practice, while several rigorous evaluations find small or null effects on final farm outcomes. Reviews of farmer field schools reveal favourable short-term participant results but weak evidence of spillovers and effects at scale. Digital communication can improve timeliness and potential reach, although device access, literacy, trust, advisory relevance and complementary markets constrain realised benefits. Commercialisation diversifies provision yet can weaken incentives to serve smallholders or address environmental public goods. Artificial intelligence may improve triage and language accessibility, but evidence of durable agronomic benefit and safe field performance is insufficient. The synthesis argues for a publicly accountable, locally adapted and hybrid advisory architecture that combines human facilitation, farmer-to-farmer networks, credible digital decision support and independent evaluation. Priority research concerns comparative financing models, subgroup-specific impacts, durable climate and ecological outcomes, AI safety, and the professional capabilities needed to coordinate diversified advisory ecosystems. Future extension systems should be judged less by messages transmitted than by farmers’ ability to make informed and feasible decisions and by the distribution and persistence of benefits.