Contemporary changes in customers' taste, demands, global competitive market and the need to promote business profitability necessitate the importance of conceptual understanding of supply chain management and design in the 21^st century. This work provides an orderly extensive literature research and investigation of methods and principle of supply chain design, modeling and simulation to illustrate conceptual understanding of supply chain management in 21^st century business and manufacturing operations. The paper also provides needed knowledge for practical supply chain management and design operation for effective and responsive supply chain management in 21^st century to utilise synergy of integration and coordination across boundaries in supply chain networks to facilitate speed decision making, quality and customer satisfaction.