The importance of agricultural knowledge systems (AKS) especially in rural communities cannot be overemphasized. AKS are important for creation, sharing and enhancing access and usage of agricultural knowledge. They link agricultural research and farms; increase adoption of good agricultural practices; improve the performance of agricultural marketing systems; and enhance effective post-harvest management. Despite the importance of agriculture to the economy and livelihoods of majority of Tanzanians, there is a consensus from scholars that the sector has been performing poorly. This is partially due to limited access to agricultural knowledge resulting into irrational decisions on agricultural activities thus dwarfing the sector. The modified Knowledge Management Processes Model guided the study in investigating how AKS can be strengthened to enhance access and usage of agricultural knowledge among stakeholders. The study adopted a pragmatic paradigm and used mixed method research by applying a survey, key informant interviews, focus group discussions (FGDs) and document reviews. Structured questionnaires were administered to 314 farmers while key informant interviews involved 57 respondents among village executives, councillors, input-suppliers, information providers, buyers, agricultural extension officers and researchers. Moreover, three FGDs involving 24 farmers were conducted. Qualitative data were analysed through classical content and constant comparison analysis, while SPSS software was used to analyse quantitative data. Quantitative and qualitative data were mixed during analysis, interpretation and discussion of results. The study identified farmers, the private sector and the government as major actors, but not working in unison. Most actors used human based systems while few used ICT and paper based systems. Actors needed agricultural knowledge on weather, farm preparation, seeds, crop maintenance, post-harvest practices, agricultural marketing and credits. Most actors shared agricultural knowledge through face-to-face interactions and mobile phones, few through internet. It was concluded that poor linkage among actors limited accessibility of agricultural knowledge. To improve accessibility to agricultural knowledge, a model for strengthening AKS usage is proposed. It is recommended that actors should be linked together and involved in enhancing access and usage of agricultural knowledge. Moreover, the proposed model should be validated before applying it. / Information Science / D. Litt. et Phil (Information Science)