With the rise of service specialization, sourcing services from multiple service providers has become the normal way of doing business. This approach has allowed service providers to deliver higher quality services and enhanced support capabilities while more affectively utilizing a greater constrained set of resources. In order for this cost savings and ability to spread risk to be realized an organization must be able to maintain a strong relationship with each service provider. In order to support the development of strong relationships in a multi-vendor environment, guidelines and reference points (technological, procedural and organizational) between the organization and the multitude of vendors being engaged must be established. These validated reference points are known as service provider interfaces (SPI). A service provider interface is a formally defined reference point which identifies some interaction between a service provider and user, customer, process or on