Covering essential medicines should be part of any plan to provide health coverage for the population, but the implementation is tricky. The example from Ghana suggests that, without a good system to monitor prescriptions and usage, drug expenditure in third party financed systems tends to outgrow revenues within a few years. What can be done to avoid that? First, a drug benefit can be defined in a restricted way, for example offering only a limited number of treatments with high public health relevance, restricting patient eligibility and setting a cap on how much each patient can receive per given period of time. Second, if patients are required to register with a primary care provider, the provider can be given a hard budget cap that is based on average cost of the benefit package times number of patients. A more advanced solution would be to develop smart phone apps (in places with mobile internet coverage and assuming that health workers use internet enabled phones already) that guide the transaction, verify patient identity with a photo and may even send the payment directly to the provider once the transaction has been recorded and verified. In any case, a functioning supply chain that keeps stock levels within defined upper and lower limits is prerequisite. In places with pre-historic annual planning, procurement and top-down distribution systems, universal coverage will remain an empty promise for those who need it most.