Dissertation (Master of International Relations)This study aimed to examine the effects of the East African Community to the Tanzanian Domestic Market: A case study of the Common Market Protocol. The study sought to achieve the following specific objectives, assessing the effects of the East African Common Market Protocol on Tanzanian Domestic Market, examining the economic relationship between the East African Community member states based on domestic market, Scrutinizing whether the Tanzanian Domestic Market benefited from the EAC-CMP, and evaluate the technical and policy challenges for implementation of the common market protocol. The research design used is a descriptive design based on cross-sectional. The study involved both open and closed-ended questions for primary data collection. The sample unit was the EAC staffs working under the EAC-CMP Department in Arusha EAC headquarters, businessmen in Arusha city centre, Professionals, farmers, students and civil servants. Findings of the study have shown that the East African Community Common Market has a modest impact on the Tanzanian Domestic Market, by adequately leading into the Tanzanian domestic market growth, free movement of goods, people, capital and services. To some extent, EAC has a modest impact on the Tanzanian economy. The study recommends a cross-border investment and foreign direct investment in Africa which requires harmonizing investment and labour laws among the regional economic communities. The East African Community should gradually relax visa and permit requirements, starting with the categories of people but with the main goal of including all community citizens. Common market policies need to be harmonized, improved, and even new ones enacted; also there was a need to observe other aspects other than policies for labour migration such as skill development be enhanced.