What are the four quadrants within the Kraljic portfolio matrix?

At the early stages In procurement and supply cycle, buyers begin segmenting current supplies in the categories, depending on their level of integration into the organization. To help get this done, the buyer may use the Kraljic portfolio matrix. The kraljic portfolio matrix segment suppliers into four categories, which are;

1) Routine 2) Bottleneck 3) Leverage 4)strategic supplier