However, a more careful examination of the existing literature leads to a more comprehensive understanding of what should be the key critical supply chain components, or "branches" of the previously identified supply chain business processes—that is, what kind of relationship the components may have that are related to suppliers and customers. Bowersox and Closs (1996) state that the emphasis on cooperation represents the synergism leading to the highest level of joint achievement. A primary-level channel participant is a business that is willing to participate in responsibility for inventory ownership or assume other financial risks, thus including primary level components. A secondary-level participant (specialized) is a business that participates in channel relationships by performing essential services for primary participants, including secondary level components, which support primary participants. Third-level channel participants and components that support primary-level channel participants and are the fundamental branches of secondary-level components may also be included.