This paper studies service systems with gatekeepers who diagnose a customer problem and then either refer the customer to an expert or attempt treatment. The probability of successful treatment by a gatekeeper decreases as the problem's complexity increases. We determine the optimal staffing...

In this paper we examine contracts to coordinate the capacity decision of a vendor who has been hired by a client to provide call center support. We consider a variety of contracts, all based on our observations of contracts used by one large vendor. We examine the role of different contract...

This paper studies outsourcing decisions for a two-level service process in which the first level serves as a gatekeeper for a second level of experts. The objective of the system operator (the client) is to minimize the sum of staffing costs, customer waiting costs, and mistreatment costs due...