Kleine und mittlere Unternehmen spielen in vielen Volkswirtschaften der Welt eine entscheidende Rolle. Der Manager des Unternehmens muss entscheiden, wie die begrenzten finanziellen Ressourcen eingesetzt werden sollen, um den Gesamtdeckungsbeitrag des Unternehmens zu maximieren. For some authors, the selection of external resources of funds to finance current asset may be one of the most important decisions while for others, the choice of capital structure does not affect the firm's market value. In order to be sure about these inspirations of various authors, the author embarked on this doctoral research project on financial resources and small and medium enterprise's performance in developing countries, taking Rwanda as a case study. Specific objectives of the research included assessing the relationship between financial resources and financial performance of small and medium enterprises, measuring the level of performance of small and medium enterprises, and identifying the status of the determinants of financial resources of small and medium enterprises (SMEs).