A DISSERTATION SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF ARTS IN RURAL DEVELOPMENT OF SOKOINE UNIVERSITY OF AGRICULTURE. MOROGORO, TANZANIAGroundwater governance is increasingly becoming critical worldwide. In Tanzania like other countries in Sub Saharan Africa, water governance including groundwater has been top on the development agenda. Nevertheless, the extent of effectiveness of groundwater governance remains unclear. To that effect, the general objective of this study was to determine effectiveness of groundwater governance with particular focus on governance structures and institutions that guide water users’ behaviour. The study employed exploratory sequential research design with two phases. In this design, qualitative data, using key informant interviews and Focus Group Discussions (FGDs), were first collected and analyzed and the results were used to refine questionnaire used in the second phase of data collection that adopted a household survey. A random sample of 90 water users including 50% females was involved in the survey. Qualitative data were analysed using content analysis. A Summated Index Scale was used to measure the extent of groundwater users’ awareness of water institutions and effectiveness of governance structures and institutions. The results show that 66.7% of the respondents depended on the groundwater (deep wells) for domestic use. The groundwater user’s perception about groundwater cleanness and the lack of other water sources were reported as the factors that influenced the use of groundwater in the study area. The mean distance from a household to a groundwater source was 249.50 metres. The results demonstrate that 50% of the respondents showed medium awareness of formal institutions; 70% and 48.9% showed high awareness of norms and values respectively. In addition, respondents showed high awareness of governance structures particularly Village Councils and Community Water Supply Organizations (COWSOs) relative to Village Water Committees. In respect to effectiveness of formal institutions in influencing groundwater governance, 56.6% of the respondents showed medium effectiveness of formal institutions compared to norms and values that showed high effectiveness by 54.4% and 55.4% respectively. In addition, the results showed statistically significant difference about awareness of institutions (P=0.0001) such that respondents showed higher awareness of the informal institutions relative to formal institutions. Furthermore, the results showed statistically significant difference between male and female responses on the effectiveness of governance institutions (P=0.0001). Female respondents reported effectiveness of governance institutions than male respondents. Based on the results, the study concludes that respondents were aware about norms and values than formal water institutions. As reported by female respondents, norms and values were more effective than formal institutions. The study recommends that further sensitization about awareness of formal institutions at local level is needed. The study recommends further investigations on factors that influence limited awareness and effectiveness of formal institutions at a local level. This will be worth for water policy planning and implementation.