Micro and Small Enterprises (MSEs) are important vehicle for economic diversification, employment creation, income generation and distribution and poverty alleviation in developing countries. They occupy prominent position in the development agenda of developing country in general and Ethiopia in particular. As a result, there is tremendous mushrooming in the number MSE business and MSE sector support institutions in the country. However, there are a number of factors that affects promotion and development of MSE business. This work critically examines factors that affect the promotion and development of MSEs that are prevailing in the countries whose severity and specificity vary from place to place and includes: access to credit, suitability and sufficiency of work premise, technical and managerial capacity of MSE operators, educational back ground and the position, market linkage, marketing and promotional activities, forecasting market demand, application of business plan, and profit generation capacity of the business and so on. The book is highly important for academicians, consultants, government agencies, entrepreneurs and for students for their academic work.