DesertationGroundnut crop production being highly practised in semi-arid areas of Shinyanga, Tabora, Dodoma and Mtwara Regions of Tanzania, has been gradually falling. The trends show that the groundnuts production has fallen from 1.13 million tons in 2015 to less than 1 million tons in 2017. The production of groundnuts like any other crops depends on seed availability while constraints associated with seed availability have altered the overall groundnut crop and its seed value chain performances. The constraints associated with the groundnut seed value chain that contribute to the poor performance of the groundnuts crop are linked with the levels of influence and importance of actors in the groundnut seed value chainhave. As a result of these levels, there are power relational dynamics that the chain actors exert on one another. The study aimed to identify actors in the groundnuts seed value chain, their roles, linkages and relational power dynamics in the chain as a result of the linkages they have. This study was descriptive and adopted a cross-sectional research design as it employed qualitative research methods that included semi-structured interviews with key informants. Focus group discussions were conducted to acquire in- depth information on relations and ties amongst actors that would explain the power actors possess. Data analysis involved identifying the extent of linkages in terms of importance and influence by analyzing the actor to actor two-dimensional linkage matrixes using the UCINET statistical software package integrated with the NETDRAW program. The identification of actors and their roles in the groundnuts seed value chain was done through content analysis while linkage and relational centrality measures were used to explain power relational changes in the chain set-up. All these aimed at determining the strength of relationships and interactions between actors hence explain the power that actors have in the value chain. Qualitative data obtained from semi-structured interviews were subjected to content analysis. The analysis involved breaking, comparing and categorising to identify levels, number of ties, linkages and extent of power in term of influence and importance the identified actors have. Findings show that, there are different actors in the groundnuts seed value chain that are differentiated by jurisdictional levels (i.e. the village and district levels). The prominent actors included Researchers, Traders, Climate Department Officials, Central Government, Agro- dealer, Agro-processors and Consumers. These were found to occupy both village and district levels. On the other hand, Farmers, Extension Officers, NGOs and CBOs, Village leaders and Middlemen were only identified at the village level. Each of these actors had different roles from which they are interconnected to form a network of linkage in two aspects, namely knowledge and income that dictate the extent of linkage among actors in-term of influence and importance. This determined the power they possess through these linkages based on the number of linkages identified among identified actors. In the knowledge aspect, NGOs, CBOs, Local Government, Researchers and Traders were found to have a higher level of influence and importance in both at the district ( Kongwa and Kiteto) and village (Mlali and Moleti) levels while farmers and extension officers were more influential at the village level only. The same actors showed to have a higher level of betweenness with values 100 and 88.89 respectively, compared to other actors. On the income aspect, Organisations (NGOs and CBOs), farmers and the climate department had a relatively higher power in terms of influence at the village level (Moleti and Mlali).The same was depicted by the Local Government and Agro-traders at the district levels (Kongwa and Kiteto). Results showed middlemen and farmers had a higher betweenness value, 9.524 and14.856 respectively compared to other actors. This explained the power to connect other actors in terms of influence and importance in the chain set up. The study concluded that, the existence of power relational changes affects linkages among actors, the performance of the groundnuts seed value chain and it plays a key function in the overall performance of the groundnuts crop. It is therefore recommended that a more emphasis on actors’ inclusion is improved through actors involvement in the chain set up in the innovation platforms. This can go hand in hand with the government boosting linkages through the improvement of strategies and policies.International Crops Research Institute for Semi-Arid Tropics (ICRISAT)