Moving from a paper-based prescribing system to a system in which physicians prescribe directly into computers represents an important but challenging transition. This article addresses 5 issues related to computerised prescribing.The first issue is that paper-based prescribing systems do not work. Rates of errors and inappropriate prescriptions are unacceptably high. Using computers to structure and check prescriptions holds great promise for ameliorating this situation.The second issue is that computerised prescribing represents a battleground in a ‘contest’ over control and content of medical practice. Eight key stakeholders with conflicting interests are vying to shape electronic prescribing. Patient, prescriber and pharmacist interest converge around key design characteristics.The third issue is that the success of electronic prescription-writing hinges on integration with clinical data and processes. While computer prescribing programs are proliferating, few have the requisite linkages required to fundamentally transform the prescribing process. Linkages with laboratory data, diagnoses and scheduling are especially critical.The fourth issue is that feedback to prescribers is vital. Computers enable advanced learning from drug-experience outcomes and should be deployed to facilitate this capability.Finally, progress depends on breakthroughs in 10 current ‘tension’ areas. Trade-offs in these tension areas can be conceptually illustrated by receiver-operating characteristic curves which show new operating characteristics required for genuine progress.While the path to electronic prescribing will be challenging, the rewards will be great. To ensure optimal results, it is critical that health professionals play a leading role in developing, designing and implementing such systems.