The latest NHS reforms in England will require all general practices to become members of general practitioner (GP) consortia. These organisations will have responsibility for commissioning the majority of health care for their local populations. This article reviews the history and evidence on impact of the previous models of GP commissioning that have been introduced in the NHS with the aim of distilling key lessons for the design, implementation and evaluation of the latest reforms. GP commissioning has the potential to generate a variety of benefits for the NHS and patients, including lowering elective and non-elective referrals, reducing waiting times, improved coordination of primary and community support services and better financial risk management. GP commissioning has also the potential to reduce patient satisfaction, increase inequalities between geographical areas and may generate substantial management and transaction costs. The GP community will need to display strong directive leadership as well as nurture a culture of collaboration and group camaraderie among practices if the GP consortia model of commissioning is to deliver the desired improvements in quality and performance. The implementation of the new GP consortia model of commissioning needs to be monitored and evaluated to ensure that the benefits are maximized and any unintended and dysfunctional effects mitigated.