The subsequent revision of sourcing policy
(after Preuss, 2009) is essential to establishing the networks and information
exchange necessary to implement sustainable upstream supply
(Kannan & Tan, 2006) and supplier capability, willingness to share information,
change practices and manage their own upstream supply
base (Johnsen et al., 2006) facilitates supply chain alignment with market
requirements. This promotes value adding activity (Chakraborty,
2010; Fisher, 1997), and competitive advantage, even where demand
or supply is subject to fluctuation (Lee, 2002).