Low effectiveness of international development aid projects is becoming an increasingly popular research problem in the academic literature. A number of scholars and practitioners are under the opinion that ineffective stakeholder management is one of the main reasons why the outcomes of many development aid projects fall below expectations. In particular, there is a popular opinion that stakeholders are often not adequately engaged in the planning activities of such projects. The current thesis is dedicated to a detailed investigation of the engagement of beneficiaries, recipients, donors and contractors in the planning stage of international development aid projects in The Gambia. There is currently no consistent framework for analyzing stakeholder engagement in such projects; therefore, this study is addressing an evident research gap. From the practical perspective, the topicality of this research derives from the fact that the election of the new President had opened The Gambia for an increased amount of foreign development aid, which attracted the attention of scientists to research problems related to the effectiveness of aid projects in this country. The study uses an exploratory research design in order to conceptualize the engagement of various stakeholder groups into the planning stage of international development aid projects in The Gambia. A mixed research methodology and the research methods of a survey and semi-structured interviews were utilized to mainly collect qualitative data and somewhat of the necessary quantitative data. After that, the researchers applied the thematic analysis for identifying themes and sub-themes relevant to the problem under investigation. The findings of the study indicate low levels of engagement from recipients, contractors, and beneficiaries in the planning stage of international development aid projects in The Gambia. The unique cultural, political, and economic characteristics of the country, institutional constraints, bureaucracy, corruption, and the inability of managers to reach targeted populations directly were found to be the most important reasons behind this regularity. Explanations of this pattern and practical recommendations for stakeholders are discussed in details in the thesis.