The theory of human service delivery entails an understanding of how people work within systems to deliver services. People are a resource unlike any other in that their value and availability can be difficult to quantify. Services are judged partly by subjective criteria, so understanding the quality that is provided by any service system can be tricky. Theorists attempt to understand how to build the best system for the best services.


Services are fundamentally intangible. They cannot be touched or handled. They exist as events and cannot be resold or shared between parties. Delivering a service to a person involves having a real person interact with her and meet her needs. For delivering any service to a person, the system designer must first consider the human element involved. The people delivering the service must be capable of interacting in a positive and effective manner.


Given that services exist as events, they tend to be more variable than other products that an organization can provide. The quality of one service to the next will differ more sharply. Organizations can improve the quality and consistency of their services only by great effort. A constant attempt must be made to gain customer feedback and to understand the ways that service can be improved. Often it is necessary to institute a training program.


The fundamental limit on the service that any organization can provide is the number of people that it has in its workforce. One person can be stretched only so far in how many tasks she can accomplish in a given amount of time. In order to increase the quality or quantity of any service, it is often necessary to increase the people involved. The more difficult the service, the more costly it will be.


Many theorists of human service delivery stress the importance of an internal credo or ideology for an organization. In order to motivate the people delivering services, and to provide them with broad guidelines, it is necessary to communicate a greater mission. By having a broader vision before them, people will be better able to process a diversity of challenges and to justify their own work. Internal ideologies tend to work best by being aspirational.