The current divisions in managing prescribing between primary and secondary care in the UK arise from separate budgetary arrangements. These divisions are neither sensible, organisationally efficient nor cost effective. Transition of patients across the interface of primary and secondary care has always been problematic, hindered by poor communication and coordination. Joint formularies would improve overall care and raise awareness of the need to consider overall costs within a unified National Health Service (NHS). There are, however, few examples of successful working of a joint formulary in the UK. It is likely that harmonisation of drug use in hospitals and in primary care will come about because of contracting and commissioning, and that it will largely be led by primary care, through the developing primary care groups (PCGs). Local decisions around availability and use of drug therapies will increasingly be superseded by the national decisions emanating from the newly formed National Institute for Clinical Effectiveness.