We evaluate the performance of two schemes to control the load imposed to the service control point (SCP), namely, call gapping and credit-based control and introduce a two level load-balancing control mechanism to provide better quality of services guarantees to IN services. Our study differs from previous studies as we consider in detail the internal organization of the SCP. Furthermore, we consider the operation of the system when servicing IN services of various levels of complexity. The complexity being measured by the number of visits to the database required to complete the service. We have been particularly interested in evaluating the call response time and system utilization since these are the two performance metrics of concern to the users and service provider, respectively. © 1998 IEEE.