One project, called Supplier Utilization Through Responsive Grouped Enterprises (SURGE), pointed to a solution. Rather than managing items individually, it sought to demonstrate the real world applicability of product family–based groupings sourcing together a traditionally problematic group of items (hydraulic tubes for fighter jets) as a means for creating longterm supplier relationships for overcoming these constraints. In theory, managing like items (those formed from common materials utilizing similar manufacturing methods) together would help suppliers overcome their individual uncertainties by managing them as a combined group. Their relative production interchangeability should help smooth out the overall demand pattern, creating the variation leveling effect depicted in Figure 4-1, resulting in greater predictability, lower costs, and improved product quality.