During the last ten years, Supply Chain Integration (SCI) has emerged as a key subject of the Supply Chain Management (SCM) literature. Despite its extended empirical investigation, very few studies have placed their focus on the information sharing perspective of supplier, internal and customer integration. On the one hand, numerous scholars theoretically argue that SCI is mainly concerned with the exchange of information, while on the other, very few have empirically examined whether information flows have a significant effect on the effectiveness of the supply chain. The present study examines the effect of SCI (measured exclusively from an 'information sharing' perspective) on customer satisfaction, supply chain performance (SCP) and financial performance. In that direction, an analytical conceptual framework is being proposed. The examination of this framework was made with the use of a newly-developed structured questionnaire that was distributed to a group of Greek manufacturing companies. Supply chain managers were selected as key respondents, due to their knowledge and expertise. After the completion of the research period, 253 usable questionnaires were returned. The reliability and the validity of the questionnaires were thoroughly examined, while research hypotheses were tested using the "Structural Equation Modeling" (SEM) technique. Results offer interesting empirical observations and managerial implications.