Drawing on social judgment theory for its theoretical underpinnings, this article presents a method for combining several descriptive indicators to yield an aggregated single summative index of the overall quality of the services received by clients in a service delivery system or program. The method described is based on the judgments of an evaluative panel and can be applied to a wide variety of populations and types of services. The delivery service index itself can be used as a dependent variable in analyses of variance or employed in correlational studies.