Implementing a national payment system for mental health is understood to be a key enabler to achieving parity of esteem between mental and physical health, and is expected to help drive up the quality of mental health services. A national payment system for mental health would enable better commissioning and more efficient services by incentivising the provision of services that achieve the best outcomes for patients. A national payment system for mental health would ensure the best services, that deliver the highest quality with best outcomes, receive the most funding. Many adults receiving care are allocated to a mental health cluster based on their need, services are then tailored according to the needs of the people they treat. In some local health economies, clusters are also used as the basis of payment replacing a system of block payment arrangements, based on historical funding rather than current service provision.