This research paper studies the effect of supply chain management (SCM) practices on the performance of companies in terms of supply chain efficiency and supply chain effectiveness. To achieve this, the study also encompasses companies that have drastically improved their internal operations, and now they find it necessary to consider relations with external customers and suppliers in the supply chain to gain further improvements in their operations. Data for this research were collected from 75 respondents of manufacturing companies. The results indicate that three variables of supply chain practices, viz. management practices (MP), customer relationship management and logistics process, are significantly and positively related to output performance. SCM is an application of systems and provides a basis for understanding processes that cut across a company’s internal departments and processes that extend outside the company as well. In this study, out of these three supply chain practices, logistics process is significantly superior as compared to MPs and customer relationship management in bringing about performance improvement. Further, the study also indicates that there is a significant difference in the impact of the three supply chain practices according to the nature of the product and size of the company.