From SSKE

Service can be defined as value co-creation, value as change thatpeople prefer, and value co-creation as a change or set of related changes that people prefer and realize as a result of their communication, planning, or other purposeful and knowledge-intensive interactions.

A simple act of competition, such as playing a game of chess, can be an example of value co-creation, benefiting the junior player to learn and benefiting the senior player to validate a performance ranking. However, the concepts of collaboration, competition, and coordination do not do justice to standardized or societal-scale patterns of value co-creation phenomena. Money (universal medium of exchange), rights (universal rule of law), and literacy (universal education) are three of the most profound service-enabling innovations ever made.

Value co-creation phenomena may be the most powerful force shaping the evolution of the world in which we live.

On value and value co-creation: A service systems perspective
Value Co-creation