It is widely acknowledged that electronic commerce presents a significant opportunity for Small- Medium-sized Enterprises (SMEs) to compete alongside larger enterprises. For SMEs in the developing world in particular, the opportunities afforded by electronic commerce for competing in a global marketplace, are also attractive. However, it has also been observed that electronic commerce poses a considerable challenge for SMEs, particularly with regard to the decisions that must be made about which of the available electronic commerce applications to adopt and to integrate into existing business operations. A number of studies have been conducted to investigate the adoption of electronic commerce by SMEs. These studies have tended to view electronic commerce adoption in terms of a dichotomous outcome: either e-commerce is adopted, or it is not. Such studies give little indication of the diffusion, or extent of usage, of individual e-commerce applications. The aim of this study was to address this gap in existing research by investigating both the level of adoption and extent of usage of e-commerce applications. In so doing, the study draws on research in the area of innovation diffusion theory. The focus of the study is on manufacturing SMES in Malaysia, and considers their use of B2B (Business-to-Business) e-commerce. The specific objectives of the study were to measure and characterise B2B e-commerce adoption and extent of usage among manufacturing SMEs in Malaysia; to identify factors associated with the adoption of B2B e-commerce in Malaysian SMEs; and to determine the impacts of that adoption. (Continues...)