It is almost universally recognized that money plays a role of high consequence in aggregate economic activity and in the day to day operations of households and business firms. But I would suggest that the theory of money has not yet been satisfactorily integrated with the pure theory of production, principally because inadequate attention has been devoted to the potential fruitfulness of money in production theory (as distinguished from its usefulness in the ordinary transactions activities of consumers and firms and its role as a private asset in various macroeconomic growth models). Indeed, it seems that the moment theoretical analysis of production functions and technological change is undertaken, money qua money simply falls by the wayside. For example, in two recent and important books that deal with theoretical (Murray Brown, Charles Ferguson) and empirical (Brown) analysis of production in a neoclassical spirit, monetary matters are not even mentioned. The theoretical and empirical research concerning the importance of money in several areas tangential to production theory is so vast that the scope of this paper must be stringently limited. I shall not deal with any of the empirical literature, but shall instead try to summarize what seem to be the most significant broad theoretical views currently held. Following this, I shall sketch in very general terms what may be a more useful way to incorporate money inproduction theory: namely, as a source of technological change.