The paper intends to explore the various developments that took place over the years in Supply Chain Management. It tries to delve deeper into this context and also highlights the imperative aspects pertinent to it by throwing light on the evolutionary aspects of concepts such as Six Sigma and others. In fact, it has tried to focus upon the innovative concept of Lean by describing in detail what it is about and how it can be very significant for the modern day large and complex forms of organizations. Details regarding this along with the methodology and its implications are also given. Furthermore, the assortment of Case Studies emphasizing its substance was also discussed with thorough analysis and illustrations with especial reference to successful lean implementation. It also draws attention to the pioneering idea of Lean manufacturings integration with Six Sigma and consequently how it facilitates the process improvement. The instances of corporations such as Lockheed Martin and Bank One are also taken into consideration and especially included in this paper.