This study investigates the Small and a medium enterprise (SME) sector in Pakistan and identifies the determinants of their business success. Theory suggests that financial resources are most important factor for growth and performance of business. The study examines the roles of financial resources and other factors (marketing strategy, technological resources, business plan, government support and business plan) in the success of SMEs. The study concludes that there is a significant relationship between business success and its determinants. It also suggests certain measures to the stakeholders for the improvement of SME sector in Pakistan.