The common objective of selection and utilization is to choose the drugs that produce maximum therapeutic effects at a minimum cost. Pharmaceutical policy-makers and prescribers agree on this point, but the constraints on each, their priorities and the information available to each differ. For policy-makers, efficacy is conceived in an impersonal, statistical manner; it includes the objective of equity and takes account of global constraints on resources. For prescribers, efficacy is conceived in terms of each individual patient, designated by name. Thus, a choice that seems rational at the national level does not necessarily result in rational use of drugs by prescribers, and rational prescriptions for each individual patient may be irrational at the global level.

It is for this reason that selection and utilization must be organized so that those who select drugs and those who prescribe them cooperate. Selection must take account of the views of prescribers and the information held by them, while utilization must take account of the views of the pharmaceutical policy-makers and the information held by them. Selection and utilization must be, at the least, acceptable to all parties involved. However, attempting to optimize selection and utilization independently will only make the whole of the pharmaceutical supply system less efficient.