Payment by results' (PbR) is probably one of the most widely debated misnomers in the NHS. At best, rather than reimbursing results, it can be considered as payment for providing collections of acute care activities. Better prevention is often cited as the only solution to sustainability, but currencies which reward prevention seemingly remain very hard to create. This review article explores the impact of legacy payment systems on health and care systems nationally and internationally. It examines alternative models, such as payment for outcomes, and questions whether any alternative payment systems may better support prevention, and fi nally achieve the 'holy grail' of a truly sustainable care system. If payment for outcomes offers a potential solution, then what are the key barriers and enablers? The case for alternative, novel metrics for success is proposed, which may better support care systems to measure their progress towards sustainability than existing indicators.ABSTRACT This somewhat baffling system of different healthcare payment currencies has largely simply evolved over time. It is remarkable that healthcare functions as effectively as it does, given the complexity of legacy payment and reimbursement systems. The important question remains as to what the impact of this is on the sustainability of health and care, and what alternative options exist, which may better align with best clinical practice, and what matters most to patients.