In addition to measurable economic consequence of an alternative investment decision, there are other important prospective consequences which cannot readily be reduced to a single common denominator stated in money terms. The extant literature of engineering economy almost entirely avoids discussion of the considerable problems which arise when attempts are made to include “irreducibles” formally in analysis, although some progress has been made in recent years in other academic disciplines. This paper, based upon some earlier work for the United States Navy, suggests a technique which can be used to include “irreducibles” along with monetary data in determining relative desirability of mutually exclusive alternative proposals. The logic of the problem and the formal structure of a desirable solution are discussed.