Let us choose to be rational. As designers we shall aim to produce the best designs possible - to optimize. To optimize from whose point of view? Ours, of course. This does not mean we should ignore society, the tenants, or the owner, nor even the architect and the contractor; their interests mould our own. For the sake of simplicity I shall assume that our values coincide with those of society. If the owner’s, the architect’s, or the contractor’s do not, why too bad for them, or for us. The present treatment should serve as a guide to take the compromise decisions that real situations force upon us; and it is directly applicable when we are employed by a branch of a government that represents the people.