The PRISMA model presented in this chapter shows that it is feasible and efficacious to improve integration functionally without—or in spite of—structural integration and merging of organizations. Implementation of the innovation should be closely monitored and adequate resources should be allocated to support the implementation and training for professionals and managers. Funding is a key issue in integration, and budget incentives and mechanisms should be adapted to the integration model. The most difficult challenge is to institutionalize the innovation, given the complexity of health care systems.