The Degree of Doctor of Philosophy 2019The use of Information and Communication Technologies (ICTs) in sharing information is very important in enhancing fish farming productivity among fish farmers. However, little is known on the linkage that exists between the use of ICTs and fish farming productivity in the Southern Highlands of Tanzania. The main objective of this study was to assess the use of ICTs to enhance information sharing for improved fish farming productivity in the Southern Highlands of Tanzania. Specifically, the study focused on establishment of the information needs of fish farmers in the study area; analyzing the influence of ICTs use in sharing agricultural information on fish farming productivity in the Southern Highlands of Tanzania; examining the determinants of the ICTs usage in sharing agricultural information among fish farmers in Tanzania, and determining the challenges facing fish farmers on the use of ICTs in sharing agricultural information. This cross sectional study was conducted in three regions, namely, Ruvuma, Mbeya and Iringa and involved twelve divisions purposively selected from six districts. The study used both quantitative and qualitative approaches in collecting data. Questionnaires, Focus Group Discussions (FGDs), observation and key informants interview were used as a data collection methods. The study involved 240 fish farmers who were randomly selected. Moreover, six key informants (one fisheries extension officer in each of the six districts) and six Focus Group Discussions (eight participants in each of the districts) were conducted in each district. Quantitative data were analysed with the aid of the Statistical Product Service SolutionP (SPSS) Version 20 while content analysis was used to analyse qualitative data. Descriptive statistics were computed to establish the profile of research participants: information needs, information accessibility, challenges of ICTs use in information sharing, and fish farming productivity level. The multiple linear regression was used to establish the influence of ICTs use and fish farming productivity. Additionally, the ordinal logistic regression model was used to examine the determinants of ICTs usage by fish farmers. The fish farmers highly needed information related to water treatment (management), spawning operations and fish preservation and processing. However, it was found that access to these categories of information was very low. Mulitple linear regression analysis revealed that the use of ICTs (mobile phones, radio, and television) for sharing agricultural information was found to influence fish productivity level (p<0.05). Moreover, it was found through ordinal logistic regression analysis that the predictors of ICTs use in information sharing were income, perceived ease of use, quantity of fish produced, attitude, household size, radio ownership and perceived usefulness. Likewise, the study findings revealed that major challenges facing fish farmers in sharing information included unfavorable radio or televisions broadcasting time, high cost of acquiring and maintenance of ICT facilities, lack of training on ICTs, and poor network connectivity. The study concluded that the more the frequency the farmers use the ICTs in sharing agricultural information on fish farming technologies, the more they could be informed about fish farming, and thus the more they could increase their fish farming productivity. It is recommended to the Government, Non-Governmental Organisations (NGOs), researchers and policy makers to consider establishing community FM radio stations in the Southern Highland regions to encourage sharing of agricultural information on fish production and knowledge to the farmers. It was also recommended that responsible organs like research institutions, policy makers and information providers should make sure that behavioural factors (perceived ease of use, perceived usefulness and attitude) that motivate individual farmers in different communities to accept the use of any ICTs are considered prior to the introduction of the respective technologies. This could assist responsible organs to design the ICT models that are relevant to fish farmers’ needs.